Discontinuous reception configuration for sidelink

ABSTRACT

Methods, systems, and devices for wireless communications are described. A user equipment (UE) may determine one or more sidelink discontinuous reception (DRX) parameters for a configured sidelink DRX cycle. The sidelink DRX parameters may be selected by the UE or may be indicated by a base station. In some cases, the UE may transmit an indication of the sidelink DRX parameters to another UE (e.g., via a sidelink communication link). A UE may discontinuously monitor for transmissions over the sidelink communication link in accordance with the sidelink DRX parameters.

CROSS REFERENCE

The present application for patent is a Continuation of U.S. applicationSer. No. 16/996,868 filed Aug. 18, 2020, which claims the benefit ofU.S. Provisional Patent Application No. 62/888,982 filed Aug. 19, 2019,assigned to the assignee hereof, and which is hereby expresslyincorporated by reference in its entirety.

INTRODUCTION

The following relates to wireless communications and more specificallyto techniques enabling power saving at a device.

Wireless communications systems are widely deployed to provide varioustypes of communication content such as voice, video, packet data,messaging, broadcast, and so on. These systems may be capable ofsupporting communication with multiple users by sharing the availablesystem resources (e.g., time, frequency, and power). Examples of suchmultiple-access systems include fourth generation (4G) systems such asLong Term Evolution (LTE) systems, LTE-Advanced (LTE-A) systems, orLTE-A Pro systems, and fifth generation (5G) systems which may bereferred to as New Radio (NR) systems. These systems may employtechnologies such as code division multiple access (CDMA), time divisionmultiple access (TDMA), frequency division multiple access (FDMA),orthogonal frequency division multiple access (OFDMA), or discreteFourier transform spread orthogonal frequency division multiplexing(DFT-S-OFDM). A wireless multiple-access communications system mayinclude a number of base stations or network access nodes, eachsimultaneously supporting communication for multiple communicationdevices, which may be otherwise known as user equipment (UE).

SUMMARY

A method of wireless communication at a first UE is described. Themethod may include determining one or more sidelink discontinuousreception (DRX) parameters for sidelink communication with a second UEand transmitting to the second UE, an indication of the one or moresidelink DRX parameters. In some examples, the indication is transmittedover a sidelink communication link with the second UE.

An apparatus for wireless communication is described. The apparatus mayinclude a processor and memory coupled to the processor. The processorand memory may be configured to cause the apparatus to determine (e.g.,at a first UE) one or more sidelink DRX parameters for sidelinkcommunication with a second UE. In some examples, the processor andmemory may be configured to transmit, to the second UE, an indication ofthe one or more sidelink DRX parameters, where the indication istransmitted over a sidelink communication link with the second UE.

Another apparatus for wireless communication is described. The apparatusmay include means for determining (e.g., at a first UE) one or moresidelink DRX parameters for sidelink communication with a second UE. Theapparatus may include means for transmitting, to the second UE, anindication of the one or more sidelink DRX parameters, where theindication is transmitted over a sidelink communication link with thesecond UE.

A non-transitory computer-readable medium storing code for wirelesscommunication is described. The code may include instructions executableby a processor to determine (e.g., at a first UE) one or more sidelinkDRX parameters for sidelink communication with a second UE. The code mayinclude instructions executable by the processor to transmit to thesecond UE, an indication of the one or more sidelink DRX parameters,where the indication is transmitted over a sidelink communication linkwith the second UE.

In some examples of the method, apparatuses, and non-transitorycomputer-readable medium described herein, determining the one or moresidelink DRX parameters may include operations, features, means, orinstructions for receiving, from a base station, a message indicatingthe one or more sidelink DRX parameters for the second UE.

In some examples of the method, apparatuses, and non-transitorycomputer-readable medium described herein, determining the one or moresidelink DRX parameters may include operations, features, means, orinstructions for selecting the one or more sidelink DRX parameters froma set of sidelink DRX parameters for the second UE.

In some examples of the method, apparatuses, and non-transitorycomputer-readable medium described herein, transmitting the indicationof the one or more sidelink DRX parameters may include operations,features, means, or instructions for transmitting an indication of adestination identity that corresponds to an identity of the second UE,where the one or more sidelink DRX parameters may be identified based onthe destination identity.

In some examples of the method, apparatuses, and non-transitorycomputer-readable medium described herein, transmitting the indicationof the one or more sidelink DRX parameters may include operations,features, means, or instructions for transmitting the indication to thesecond UE via sidelink control information (SCI), or a medium accesscontrol (MAC) control element, or a combination thereof.

Some examples of the method, apparatuses, and non-transitorycomputer-readable medium described herein may further includeoperations, features, means, or instructions for transmitting the DCI tothe second UE on a physical sidelink control channel (PSCCH).

Some examples of the method, apparatuses, and non-transitorycomputer-readable medium described herein may further includeoperations, features, means, or instructions for transmitting a messageto the second UE in accordance with the one or more sidelink DRXparameters.

Some examples of the method, apparatuses, and non-transitorycomputer-readable medium described herein may further includeoperations, features, means, or instructions for receiving, from a basestation, an indication of one or more DRX parameters for communicatingwith the base station, where the one or more DRX parameters may bedifferent from the one or more sidelink DRX parameters, anddiscontinuously monitoring for a transmission from the base station inaccordance with the one or more DRX parameters.

In some examples of the method, apparatuses, and non-transitorycomputer-readable medium described herein, discontinuously monitoringfor the transmission from the base station may include operations,features, means, or instructions for powering down a first poweramplifier for communicating with the base station in accordance with theone or more DRX parameters, the method further including, and poweringdown a second power amplifier for the sidelink communication link inaccordance with the one or more sidelink DRX parameters.

In some examples of the method, apparatuses, and non-transitorycomputer-readable medium described herein, respective configurations ofthe one or more DRX parameters and the one or more sidelink DRXparameters may be based on a first carrier for communicating with thebase station and a second carrier for the sidelink communication link, afirst frequency range for communicating with the base station and asecond frequency range for the sidelink communication link, one or morebands of a primary land mobile network for the sidelink communicationlink, or a combination thereof.

Some examples of the method, apparatuses, and non-transitorycomputer-readable medium described herein may further includeoperations, features, means, or instructions for receiving, from a basestation, an indication of one or more DRX parameters for communicatingwith the base station, where the one or more DRX parameters may be thesame as the one or more sidelink DRX parameters, and discontinuouslymonitoring for a transmission from the base station in accordance withthe one or more DRX parameters.

In some examples of the method, apparatuses, and non-transitorycomputer-readable medium described herein, the one or more sidelink DRXparameters includes an ON duration, an offset duration, an inactivitytimer, one or more cycle durations, a cycle timer, or any combinationthereof.

In some examples of the method, apparatuses, and non-transitorycomputer-readable medium described herein, the first UE may be within acoverage area of a base station. In some examples of the method,apparatuses, and non-transitory computer-readable medium describedherein, the first UE and the second UE may be outside a coverage area ofa base station.

A method of wireless communication at a first UE is described. Themethod may include determining one or more sidelink DRX parameters forsidelink communication with a second UE. The method may further includediscontinuously monitoring (e.g., at the first UE) a sidelinkcommunication link for a transmission from the second UE in accordancewith the one or more sidelink DRX parameters.

An apparatus for wireless communication is described. The apparatus mayinclude a processor and memory coupled to the processor. The processorand memory may be configured to determine (e.g., at a first UE) one ormore sidelink DRX parameters for sidelink communication with a secondUE. In some examples, the processor and memory may be configured todiscontinuously monitor a sidelink communication link for a transmissionfrom the second UE in accordance with the one or more sidelink DRXparameters.

Another apparatus for wireless communication is described. The apparatusmay include means for determining (e.g., at a first UE) one or moresidelink DRX parameters for sidelink communication with a second UE. Insome examples, the apparatus may include means for discontinuouslymonitoring a sidelink communication link for a transmission from thesecond UE in accordance with the one or more sidelink DRX parameters.

A non-transitory computer-readable medium storing code for wirelesscommunication is described. The code may include instructions executableby a processor to determine (e.g., at a first UE) one or more sidelinkDRX parameters for sidelink communication with a second UE. In someexamples, the code may include instructions executable by a processor todiscontinuously monitor a sidelink communication link for a transmissionfrom the second UE in accordance with the one or more sidelink DRXparameters.

Some examples of the method, apparatuses, and non-transitorycomputer-readable medium described herein may further includeoperations, features, means, or instructions for receiving, from thesecond UE, an indication of the one or more sidelink DRX parameters, theindication received over the sidelink communication link, where the oneor more sidelink DRX parameters may be determined based on the receivedindication.

Some examples of the method, apparatuses, and non-transitorycomputer-readable medium described herein may further includeoperations, features, means, or instructions for receiving theindication of the one or more sidelink DRX parameters from the second UEvia SCI, or a MAC control element, or a combination thereof.

Some examples of the method, apparatuses, and non-transitorycomputer-readable medium described herein may further includeoperations, features, means, or instructions for receiving the DCI fromthe second UE on a PSCCH.

Some examples of the method, apparatuses, and non-transitorycomputer-readable medium described herein may further includeoperations, features, means, or instructions for receiving, from a basestation, a message indicating the one or more sidelink DRX parametersfor the second UE, where the one or more sidelink DRX parameters may bedetermined based on the received indication.

Some examples of the method, apparatuses, and non-transitorycomputer-readable medium described herein may further includeoperations, features, means, or instructions for identifying the one ormore sidelink DRX parameters based on a destination identitycorresponding to an identity of the first UE, where discontinuouslymonitoring the sidelink communication link may be based on identifyingthe one or more sidelink DRX parameters.

In some examples of the method, apparatuses, and non-transitorycomputer-readable medium described herein, the one or more sidelink DRXparameters includes an ON duration, an offset duration, an inactivitytimer, one or more cycle durations, a cycle timer, or any combinationthereof. In some examples of the method, apparatuses, and non-transitorycomputer-readable medium described herein, the first UE may be outside acoverage area of a base station.

A method of wireless communication at a base station is described. Themethod may include configuring one or more sidelink DRX parameters forsidelink communication between a first UE and a second UE over asidelink communication link. The method may further includetransmitting, to the first UE, a message indicating the one or moresidelink DRX parameters.

An apparatus for wireless communication at a base station is described.The apparatus may include a processor and memory coupled to theprocessor. The processor and memory may configure one or more sidelinkDRX parameters for sidelink communication between a first UE and asecond UE over a sidelink communication link. The processor and memorymay be configured to transmit, to the first UE, a message indicating theone or more sidelink DRX parameters.

Another apparatus for wireless communication at a base station isdescribed. The apparatus may include means for configuring one or moresidelink DRX parameters for sidelink communication between a first UEand a second UE over a sidelink communication link. In some examples,the apparatus may include means for transmitting, to the first UE, amessage indicating the one or more sidelink DRX parameters.

A non-transitory computer-readable medium storing code for wirelesscommunication at a base station is described. The code may includeinstructions executable by a processor to configure one or more sidelinkDRX parameters for sidelink communication between a first UE and asecond UE over a sidelink communication link. In some examples, the codemay include instructions executable by a processor to transmit, to thefirst UE, a message indicating the one or more sidelink DRX parameters.

In some examples of the method, apparatuses, and non-transitorycomputer-readable medium described herein, transmitting the messageindicating the one or more sidelink DRX parameters may includeoperations, features, means, or instructions for determining an identityof the second UE, and transmitting, as part of the message, anindication of a destination identity that corresponds to the identity ofthe second UE, where the one or more sidelink DRX parameters may beidentified based on the destination identity.

Some examples of the method, apparatuses, and non-transitorycomputer-readable medium described herein may further includeoperations, features, means, or instructions for transmitting, to thesecond UE, a second message indicating the one or more sidelink DRXparameters.

Some examples of the method, apparatuses, and non-transitorycomputer-readable medium described herein may further includeoperations, features, means, or instructions for configuring one or moreDRX parameters for communicating with the first UE, where the one ormore DRX parameters may be different from the one or more sidelink DRXparameters, and transmitting, to the first UE, an indication of the oneor more DRX parameters.

In some examples of the method, apparatuses, and non-transitorycomputer-readable medium described herein, respective configurations ofthe one or more DRX parameters and the one or more sidelink DRXparameters may be based on a first carrier for communicating with thebase station and a second carrier for the sidelink communication link, afirst frequency range for communicating with the base station and asecond frequency range for the sidelink communication link, one or morebands of a primary land mobile network for the sidelink communicationlink, or a combination thereof.

Some examples of the method, apparatuses, and non-transitorycomputer-readable medium described herein may further includeoperations, features, means, or instructions for configuring one or moreDRX parameters for communicating with the first UE, where the one ormore DRX parameters may be the same as the one or more sidelink DRXparameters, and transmitting, to the first UE, an indication of the oneor more DRX parameters.

In some examples of the method, apparatuses, and non-transitorycomputer-readable medium described herein, the one or more sidelink DRXparameters includes an ON duration, an offset duration, an inactivitytimer, one or more cycle durations, a cycle timer, or any combinationthereof.

In some examples of the method, apparatuses, and non-transitorycomputer-readable medium described herein, the first UE may be within acoverage area of the base station and the second UE may be outside thecoverage area of the base station.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 illustrates an example of a system for wireless communicationsthat supports DRX configuration for sidelink in accordance with one ormore aspects of the present disclosure.

FIGS. 2A, 2B, and 2C illustrate examples of wireless communicationssystems that support DRX configurations for sidelink in accordance withone or more aspects of the present disclosure.

FIGS. 3A, 3B, and 3C illustrates an example of a wireless communicationsystem that supports DRX configurations for sidelink in accordance withone or more aspects of the present disclosure.

FIG. 4 illustrates an example of DRX configurations that support DRXconfigurations for sidelink in accordance with one or more aspects ofthe present disclosure.

FIGS. 5 and 6 show block diagrams of devices that support DRXconfigurations for sidelink in accordance with one or more aspects ofthe present disclosure.

FIG. 7 shows a block diagram of a UE communications manager thatsupports DRX configurations for sidelink in accordance with one or moreaspects of the present disclosure.

FIG. 8 shows a diagram of a system including a device that supports DRXconfigurations for sidelink in accordance with one or more aspects ofthe present disclosure.

FIGS. 9 and 10 show block diagrams of devices that support DRXconfigurations for sidelink in accordance with one or more aspects ofthe present disclosure.

FIG. 11 shows a block diagram of a base station communications managerthat supports DRX configurations for sidelink in accordance with one ormore aspects of the present disclosure.

FIG. 12 shows a diagram of a system including a device that supports DRXconfigurations for sidelink in accordance with one or more aspects ofthe present disclosure.

FIGS. 13 through 16 show flowcharts illustrating methods that supportDRX configurations for sidelink in accordance with one or more aspectsof the present disclosure.

DETAILED DESCRIPTION

A wireless communications system may support both access links andsidelinks for communications between wireless devices. An access linkmay refer to a communication link between a UE and a base station. Forexample, an access link may support uplink signaling, downlinksignaling, connection establishment and synchronization procedures, etc.A sidelink may refer to communication links between similar wirelessdevices (e.g., a communication link between UEs or a backhaulcommunication link between base stations). It is noted that whilevarious examples provided herein are discussed for UE sidelink devices,such sidelink techniques may be used for any type of wireless devicesthat use sidelink communications. For example, a sidelink may supportdevice-to-device (D2D) communications, vehicle-to-everything (V2X)and/or vehicle-to-vehicle (V2V) communications, message relaying,discovery signaling, beacon signaling, or any combination of these orother signals transmitted over-the-air from one UE to one or more otherUEs.

Sidelink communications may be utilized by UEs in various states ofcoverage within a cell. For example, sidelink communications may includecommunications between two UEs that are both within a coverage areaprovided by a base station, between one UE in coverage and another UEoutside of coverage (e.g., an out-of-coverage UE), or between two UEsthat are both outside of coverage. As these examples illustrate, theremay be cases in which a UE may communicate over a sidelink while outsidethe coverage of a base station, and the UE may therefore lack a directconnection with the network (e.g., via a radio resource control (RRC)link). As a result, an out-of-coverage UE may irregularly monitor forpaging signals from the network and may also be unaware of one or moreother UEs that may be transmitting information to the out-of-coverage UEvia the sidelink communication link. The out-of-coverage UE may thusmonitor sidelink resource pools for sidelink transmissions from otherUEs. Likewise, UEs that are in-coverage may be unaware of when sidelinktransmissions may be sent, and the in-coverage UEs may accordinglymonitor sidelink resource pools for transmissions from another UE. Insome cases, monitoring for one or more sidelink transmissions by variousUEs may be continuous to reduce the number of sidelink transmissionsthat are missed, and the UEs may consume excess power as a result.

However, as described herein, power saving techniques for sidelinkcommunications may be used to enable reduced power consumption andextended battery life. For example, a UE may be configured with asidelink DRX cycle, which may enable the UE to discontinuously monitorfor transmissions from another UE over a sidelink communication link. Assuch, one or more sidelink DRX parameters may be provided to UEs to usefor sidelink power savings, where the UEs may be in various states ofcoverage (e.g., with a base station). As a first example, a UE may bein-coverage with a base station and the in-coverage UE may receive thesidelink DRX parameters from the network. The UE may then transmit orrelay an indication of the sidelink DRX parameters to another UE (e.g.,an out-of-coverage UE) over a sidelink communication link. In othercases, multiple UEs may receive the sidelink DRX parameters from thebase station. Additionally or alternatively, an in-coverage UE mayselect the sidelink DRX parameters, and may transmit an indication ofthe parameters to one or more other UEs. In any case, the sidelink DRXparameters may be used by the UEs to periodically monitor a sidelinkcommunication link for transmissions from another UE while powering downone or more components (e.g., power amplifiers, radio frequency (RF)chains, etc.) when irregularly monitoring the sidelink communicationlink. In some other examples, a UE that is out-of-coverage may determineDRX parameters and indicate the DRX parameters to other UEs. Forexample, in some cases one or more UEs may negotiate DRX parameters andmay indicate the determined DRX parameters to other UEs in the network.

In some examples, there may be separate configurations for the sidelinkDRX cycle and other DRX cycles for communications between a UE and abase station (e.g., corresponding to a Uu interface between a mobiledevice and a radio access network). The separate configuration of thesidelink DRX cycle and other DRX cycles may be based on the use ofresources for sidelink communications and resources for communicationwith the base station. For instance, respective carriers (e.g.,component carriers (CCs)) may be used for sidelink communications andcommunications over an access link, and different DRX configurations mayaccordingly be used for the sidelink and access link. In other cases,different DRX configurations may be used for sidelink communications andaccess link communications on a same carrier. Additionally oralternatively, a sidelink DRX cycle may be synchronized with a DRX cycleused for communicating with a base station, where the synchronization ofthe DRX cycles may enable a UE to efficiently transmit to otherout-of-coverage UEs, as well as for the UE to receive uplinktransmissions (e.g., to be relayed to the base station) from theout-of-coverage UEs. In some cases, a UE that relays transmissionsto/from other UEs may indicate its DRX parameters (e.g., as configuredfor its link with the base station (e.g., the Uu interface)) to theother UEs. As such, the DRX parameters may be signaled over the sidelinkto the other UEs.

Aspects of the disclosure are initially described in the context ofwireless communications systems. Further examples are then provided ofsignaling between devices in wireless communications systems and DRXconfigurations used by a UE for sidelink communications. Aspects of thedisclosure are further illustrated by and described with reference toapparatus diagrams, system diagrams, and flowcharts that relate to DRXconfigurations for sidelink.

FIG. 1 illustrates an example of a wireless communications system 100that that support DRX configurations for sidelink in accordance with oneor more aspects of the present disclosure. The wireless communicationssystem 100 may include base stations 105, UEs 115, and a core network130. In some examples, the wireless communications system 100 may be anLTE network, an LTE-A network, an LTE-A Pro network, or an NR network.In some cases, the wireless communications system 100 may supportenhanced broadband communications, ultra-reliable (e.g., missioncritical) communications, low latency communications, communicationswith low-cost and low-complexity devices, or any combination thereof.

Base stations 105 may be dispersed throughout a geographic area to formthe wireless communications system 100 and may be devices in differentforms or having different capabilities. Base stations 105 and UEs 115may wirelessly communicate via one or more communication links 125. Eachbase station 105 may provide a coverage area 110 over which UEs 115 andthe base station 105 may establish communication links 125. The coveragearea 110 may be an example of a geographic area over which a basestation 105 and a UE 115 support the communication of signals accordingto one or more radio access technologies.

UEs 115 may be dispersed throughout a coverage area 110 of the wirelesscommunications system 100, and each UE 115 may be stationary, or mobile,or both at different times. UEs 115 may be devices in different forms orhaving different capabilities. Some example UEs 115 are illustrated inFIG. 1 . The UEs 115 described herein may be able to communicate withvarious types of devices, such as other UEs 115, base stations 105,and/or network equipment (e.g., core network nodes, relay devices,integrated access and backhaul (IAB) nodes, or other network equipment),as described with reference to FIG. 1 .

Base stations 105 may communicate with the core network 130, or with oneanother, or both. For example, base stations 105 may interface with thecore network 130 through backhaul links 120 (e.g., via an S1, N2, N3, orother interface). Base stations 105 may communicate with one anotherover backhaul links 120 (e.g., via an X2, Xn, or other interface) eitherdirectly (e.g., directly between base stations 105), or indirectly(e.g., via core network 130), or both. In some examples, backhaul links120 may be or include one or more wireless links. One or more of basestations 105 described herein may include or may be referred to by aperson of ordinary skill in the art as a base transceiver station, aradio base station, an access point, a radio transceiver, a NodeB, aneNodeB (eNB), a next-generation NodeB or giga-NodeB (either of which maybe referred to as a gNB), a Home NodeB, a Home eNodeB, or other suitableterminology. In some examples, a UE 115 may communicate with the corenetwork 130 through communication link 135.

A UE 115 may include or may be referred to as a mobile device, awireless device, a remote device, a handheld device, or a subscriberdevice, or some other suitable terminology, where the “device” may alsobe referred to as a unit, a station, a terminal, or a client, amongother examples. A UE 115 may also include or may be referred to as apersonal electronic device such as a cellular phone, a personal digitalassistant (PDA), a tablet computer, a laptop computer, or a personalcomputer. In some examples, a UE 115 may include or be referred to as awireless local loop (WLL) station, an Internet of Things (IoT) device,an Internet of Everything (IoE) device, a machine type communications(MTC) device, or the like, which may be implemented in various objectssuch as appliances, vehicles, meters, or the like.

The UEs 115 described herein may be able to communicate with varioustypes of devices, such as other UEs 115 that may sometimes act as relaysas well as base stations 105 and network equipment including macro eNBsor gNBs, small cell eNBs or gNBs, relay base stations, and the like, asdescribed with reference to FIG. 1 .

UEs 115 and base stations 105 may wirelessly communicate with oneanother via one or more communication links 125 over one or morecarriers. The term “carrier” may refer to a set of radio frequencyspectrum resources having a defined physical layer structure forsupporting communication links 125. For example, a carrier used for acommunication link 125 may include a portion of a radio frequencyspectrum band (e.g., a bandwidth part (BWP)) that is operated accordingto physical layer channels for a given radio access technology (e.g.,LTE, LTE-A, LTE-A Pro, NR). Each physical layer channel may carryacquisition signaling (e.g., synchronization signals, systeminformation), control signaling that coordinates operation for thecarrier, user data, or other signaling. The wireless communicationssystem 100 may support communication with a UE 115 using carrieraggregation or multi-carrier operation. A UE 115 may be configured withmultiple downlink component carriers and one or more uplink componentcarriers according to a carrier aggregation configuration. Carrieraggregation may be used with both frequency division duplexing (FDD) andtime division duplexing (TDD) component carriers.

In some examples (e.g., in a carrier aggregation configuration), acarrier may also have acquisition signaling or control signaling thatcoordinates operations for other carriers. A carrier may be associatedwith a frequency channel (e.g., an evolved universal mobiletelecommunication system terrestrial radio access (E-UTRA) absoluteradio frequency channel number (EARFCN)) and may be positioned accordingto a channel raster for discovery by UEs 115. A carrier may be operatedin a standalone mode where initial acquisition and connection may beconducted by UEs 115 via the carrier, or the carrier may be operated ina non-standalone mode where a connection is anchored using a differentcarrier (e.g., of the same or a different radio access technology).

Communication links 125 shown in the wireless communications system 100may include uplink transmissions from a UE 115 to a base station 105, ordownlink transmissions from a base station 105 to a UE 115. Carriers maycarry downlink or uplink communications (e.g., in an FDD mode) or may beconfigured to carry downlink and uplink communications (e.g., in a TDDmode).

A carrier may be associated with a particular bandwidth of the radiofrequency spectrum, and in some examples the carrier bandwidth may bereferred to as a “system bandwidth” of the carrier or the wirelesscommunications system 100. For example, the carrier bandwidth may be oneof a number of predetermined bandwidths for carriers of a particularradio access technology (e.g., 1.4, 3, 5, 10, 15, 20, 40, or 80megahertz (MHz)). Devices of the wireless communications system 100(e.g., base stations 105, UEs 115, or both) may have hardwareconfigurations that support communications over a particular carrierbandwidth or may be configurable to support communications over one of aset of carrier bandwidths. In some examples, the wireless communicationssystem 100 may include base stations 105 and/or UEs 115 that supportsimultaneous communications via carriers associated with multiplecarrier bandwidths. In some examples, each served UE 115 may beconfigured for operating over portions (e.g., a sub-band, a BWP) or allof a carrier bandwidth.

Signal waveforms transmitted over a carrier may be made up of multiplesubcarriers (e.g., using multi-carrier modulation (MCM) techniques suchas orthogonal frequency division multiplexing (OFDM) or discrete Fouriertransform spread OFDM (DFT-S-OFDM)). In a system employing MCMtechniques, a resource element may consist of one symbol period (e.g., aduration of one modulation symbol) and one subcarrier, where the symbolperiod and subcarrier spacing are inversely related. The number of bitscarried by each resource element may depend on the modulation scheme(e.g., the order of the modulation scheme, the coding rate of themodulation scheme, or both). Thus, the more resource elements that a UE115 receives and the higher the order of the modulation scheme, thehigher the data rate may be for the UE 115. A wireless communicationsresource may refer to a combination of a radio frequency spectrumresource, a time resource, and a spatial resource (e.g., spatial layersor beams), and the use of multiple spatial layers may further increasethe data rate or data integrity for communications with a UE 115.

One or more numerologies for a carrier may be supported, where anumerology may include a subcarrier spacing (Δf) and a cyclic prefix. Acarrier may be divided into BWPs having the same or differentnumerologies. In some examples, a UE 115 may be configured with multipleBWPs. In some cases, a single BWP for a carrier is active at a giventime, and communications for the UE 115 may be restricted to activeBWPs.

Time intervals for base stations 105 or UEs 115 may be expressed inmultiples of a basic time unit which may, for example, refer to asampling period of T_(s)=1/(Δf_(max)·N_(f)) seconds, where Δf_(max) mayrepresent the maximum supported subcarrier spacing, and N_(f) mayrepresent the maximum supported discrete Fourier transform (DFT) size.Time intervals of a communications resource may be organized accordingto radio frames each having a specified duration (e.g., 10 milliseconds(ms)). Each radio frame may be identified by a system frame number (SFN)(e.g., ranging from 0 to 1023).

Each frame may include multiple consecutively numbered subframes orslots, and each subframe or slot may have the same duration. In somecases, a frame may be divided (e.g., in the time domain) into subframes,and each subframe may be further divided into a number of slots.Alternatively, each frame may include a variable number of slots, andthe number of slots may depend on subcarrier spacing. Each slot mayinclude a number of symbol periods (e.g., depending on the length of thecyclic prefix prepended to each symbol period). In some wirelesscommunications systems 100, a slot may further be divided into multiplemini-slots containing one or more symbols. Excluding the cyclic prefix,each symbol period may contain one or more (e.g., N_(f)) samplingperiods. The duration of a symbol period may depend on the subcarrierspacing or frequency band of operation.

A subframe, a slot, a mini-slot, or a symbol may be the smallestscheduling unit (e.g., in the time domain) of the wirelesscommunications system 100 and may be referred to as a transmission timeinterval (TTI). In some cases, the TTI duration (e.g., the number ofsymbol periods in a TTI) may be variable. Additionally or alternatively,the smallest scheduling unit of the wireless communications system 100may be dynamically selected (e.g., in bursts of shortened TTIs (sTTIs)).

Physical channels may be multiplexed on a carrier according to varioustechniques. A physical control channel and a physical data channel maybe multiplexed on a downlink carrier, for example, using time divisionmultiplexing (TDM) techniques, frequency division multiplexing (FDM)techniques, or hybrid TDM-FDM techniques. A control region (e.g., acontrol resource set (CORESET)) for a physical control channel may bedefined by a number of symbol periods and may extend across the systembandwidth or a subset of the system bandwidth of the carrier. One ormore control regions (e.g., CORESETs) may be configured for a set of UEs115. For example, UEs 115 may monitor or search control regions forcontrol information according to one or more search space sets, and eachsearch space set may include one or multiple control channel candidatesin one or more aggregation levels arranged in a cascaded manner. Anaggregation level for a control channel candidate may refer to a numberof control channel resources (e.g., control channel elements (CCEs))associated with encoded information for a control information formathaving a given payload size. Search space sets may include common searchspace sets configured for sending control information to multiple UEs115 and UE-specific search space sets for sending control information toa specific UE 115.

Each base station 105 may provide communication coverage via one or morecells, for example a macro cell, a small cell, a hot spot, or othertypes of cells, or various combinations thereof. The term “cell” mayrefer to a logical communication entity used for communication with abase station 105 (e.g., over a carrier) and may be associated with anidentifier for distinguishing neighboring cells (e.g., a physical cellidentifier (PCID), a virtual cell identifier (VCID), or others). In someexamples, a cell may also refer to a geographic coverage area 110 or aportion of a geographic coverage area 110 (e.g., a sector) over whichthe logical communication entity operates. Such cells may range fromsmaller areas (e.g., a structure, a subset of structure) to larger areasdepending on various factors such as the capabilities of the basestation 105. For example, a cell may be or include a building, a subsetof a building, exterior spaces between or overlapping with geographiccoverage areas 110, or the like.

A macro cell generally covers a relatively large geographic area (e.g.,several kilometers in radius) and may allow unrestricted access by UEs115 with service subscriptions with the network provider supporting themacro cell. A small cell may be associated with a lower-powered basestation 105, as compared with a macro cell, and a small cell may operatein the same or different (e.g., licensed, unlicensed) frequency bands asmacro cells. Small cells may provide unrestricted access to UEs 115 withservice subscriptions with the network provider or may providerestricted access to UEs 115 having an association with the small cell(e.g., UEs 115 in a closed subscriber group (CSG), UEs 115 associatedwith users in a home or office, and the like). A base station 105 maysupport one or multiple cells and may also support communications overthe one or more cells using one or multiple component carriers. In someexamples, a carrier may support multiple cells, and different cells maybe configured according to different protocol types (e.g., MTC,narrowband IoT (NB-IoT), enhanced mobile broadband (eMBB), or others)that may provide access for different types of devices.

In some examples, a base station 105 may be movable and thereforeprovide communication coverage for a moving geographic coverage area110. In some examples, different geographic coverage areas 110associated with different technologies may overlap, but the differentgeographic coverage areas 110 may be supported by the same base station105. In other examples, overlapping geographic coverage areas 110associated with different technologies may be supported by differentbase stations 105. The wireless communications system 100 may include,for example, a heterogeneous network in which different types of basestations 105 provide coverage for various geographic coverage areas 110using the same or different radio access technologies.

The wireless communications system 100 may support synchronous orasynchronous operation. For synchronous operation, the base stations 105may have similar frame timings, and transmissions from different basestations 105 may be approximately aligned in time. For asynchronousoperation, the base stations 105 may have different frame timings, andtransmissions from different base stations 105 may, in some examples, beirregularly aligned in time. The techniques described herein may be usedfor either synchronous or asynchronous operations.

Some UEs 115, such as MTC or IoT devices, may be low cost or lowcomplexity devices and may provide for automated communication betweenmachines (e.g., via Machine-to-Machine (M2M) communication). M2Mcommunication or MTC may refer to data communication technologies thatallow devices to communicate with one another or a base station 105without human intervention. In some examples, M2M communication or MTCmay include communications from devices that integrate sensors or metersto measure or capture information and relay such information to acentral server or application program that makes use of the informationor presents the information to humans interacting with the applicationprogram. Some UEs 115 may be designed to collect information or enableautomated behavior of machines or other devices. Examples ofapplications for MTC devices include smart metering, inventorymonitoring, water level monitoring, equipment monitoring, healthcaremonitoring, wildlife monitoring, weather and geological eventmonitoring, fleet management and tracking, remote security sensing,physical access control, and transaction-based business charging.

Some UEs 115 may be configured to employ operating modes that reducepower consumption, such as half-duplex communications (e.g., a mode thatsupports one-way communication via transmission or reception, but nottransmission and reception simultaneously). In some examples,half-duplex communications may be performed at a reduced peak rate.Other power conservation techniques for UEs 115 include entering a powersaving deep sleep mode when not engaging in active communications,operating over a limited bandwidth (e.g., according to narrowbandcommunications), or a combination of these techniques. For example, someUEs 115 may be configured for operation using a narrowband protocol typethat is associated with a predefined portion or range (e.g., set ofsubcarriers or resource blocks (RBs)) within a carrier, within aguard-band of a carrier, or outside of a carrier.

The wireless communications system 100 may be configured to supportultra-reliable communications or low-latency communications, or variouscombinations thereof. For example, the wireless communications system100 may be configured to support ultra-reliable low-latencycommunications (URLLC) or mission critical communications. UEs 115 maybe designed to support ultra-reliable, low-latency, or criticalfunctions (e.g., mission critical functions). Ultra-reliablecommunications may include private communication or group communicationand may be supported by one or more mission critical services such asmission critical push-to-talk (MCPTT), mission critical video (MCVideo),or mission critical data (MCData). Support for mission criticalfunctions may include prioritization of services, and mission criticalservices may be used for public safety or general commercialapplications. The terms ultra-reliable, low-latency, mission critical,and ultra-reliable low-latency may be used interchangeably herein.

In some cases, a UE 115 may also be able to communicate directly withother UEs 115 over a device-to-device (D2D) communication link (e.g.,using a peer-to-peer (P2P) or D2D protocol). One or more UEs 115utilizing D2D communications may be within the geographic coverage area110 of a base station 105. Other UEs 115 in such a group may be outsidethe geographic coverage area 110 of a base station 105 or be otherwiseunable to receive transmissions from a base station 105. In some cases,groups of UEs 115 communicating via D2D communications may utilize aone-to-many (1:M) system in which each UE 115 transmits to every otherUE 115 in the group. In some examples, a base station 105 facilitatesthe scheduling of resources for D2D communications. In other cases, D2Dcommunications are carried out between UEs 115 without the involvementof a base station 105.

In some systems, the D2D communication link (e.g., a sidelinkcommunication link 135) may be an example of a communication channel,such as a sidelink communication channel, between vehicles (e.g., UEs115). In some examples, vehicles may communicate usingvehicle-to-everything (V2X) communications, vehicle-to-vehicle (V2V)communications, or some combination of these. A vehicle may signalinformation related to traffic conditions, signal scheduling, weather,safety, emergencies, or any other information relevant to a V2X system.In some cases, vehicles in a V2X system may communicate with roadsideinfrastructure, such as roadside units, or with the network via one ormore network nodes (e.g., base stations 105) using vehicle-to-network(V2N) communications, or with both.

The core network 130 may provide user authentication, accessauthorization, tracking, Internet Protocol (IP) connectivity, and otheraccess, routing, or mobility functions. The core network 130 may be anevolved packet core (EPC) or 5G core (5GC), which may include at leastone control plane entity that manages access and mobility (e.g., amobility management entity (MME), an access and mobility managementfunction (AMF)) and at least one user plane entity that routes packetsor interconnects to external networks (e.g., a serving gateway (S-GW), aPacket Data Network (PDN) gateway (P-GW), a user plane function (UPF)).The control plane entity may manage non-access stratum (NAS) functionssuch as mobility, authentication, and bearer management for UEs 115served by base stations 105 associated with the core network 130. UserIP packets may be transferred through the user plane entity, which mayprovide IP address allocation as well as other functions. The user planeentity may be connected to the network operators IP services. Theoperators IP services may include access to the Internet, Intranet(s),an IP Multimedia Subsystem (IMS), or a Packet-Switched StreamingService.

Some of the network devices, such as a base station 105, may includesubcomponents such as an access network entity, which may be an exampleof an access node controller (ANC). Each access network entity maycommunicate with UEs 115 through a number of other access networktransmission entities, which may be referred to as radio heads, smartradio heads, or transmission/reception points (TRPs). Each accessnetwork transmission entity may include one or more antenna panels. Insome configurations, various functions of each access network entity orbase station 105 may be distributed across various network devices(e.g., radio heads and ANCs) or consolidated into a single networkdevice (e.g., a base station 105).

The wireless communications system 100 may operate using one or morefrequency bands, for example, in the range of 300 megahertz (MHz) to 300gigahertz (GHz). Generally, the region from 300 MHz to 3 GHz is known asthe ultra-high frequency (UHF) region or decimeter band, since thewavelengths range from approximately one decimeter to one meter inlength. UHF waves may be blocked or redirected by buildings andenvironmental features, but the waves may penetrate structuressufficiently for a macro cell to provide service to UEs 115 locatedindoors. Transmission of UHF waves may be associated with smallerantennas and shorter ranges (e.g., less than 100 kilometers) compared totransmission using the smaller frequencies and longer waves of the highfrequency (HF) or very high frequency (VHF) portion of the spectrumbelow 300 MHz.

The electromagnetic spectrum is often subdivided, based onfrequency/wavelength, into various classes, bands, channels, etc. In 5GNR two initial operating bands have been identified as frequency rangedesignations FR1 (410 MHz-7.125 GHz) and FR2 (24.25 GHz-52.6 GHz). Thefrequencies between FR1 and FR2 are often referred to as mid-bandfrequencies. Although a portion of FR1 is greater than 6 GHz, FR1 isoften referred to (interchangeably) as a “Sub-6 GHz” band in variousdocuments and articles. A similar nomenclature issue sometimes occursregarding FR2, which is often referred to (interchangeably) as a“millimeter wave” band in documents and articles, despite beingdifferent from the extremely high frequency (EHF) band (30 GHz-300 GHz)which is identified by the International Telecommunications Union (ITU)as a “millimeter wave” band.

With the above aspects in mind, unless specifically stated otherwise, itshould be understood that the term “sub-6 GHz” or the like if usedherein may broadly represent frequencies that may be less than 6 GHz,may be within FR1, or may include mid-band frequencies. Further, unlessspecifically stated otherwise, it should be understood that the term“millimeter wave” or the like if used herein may broadly representfrequencies that may include mid-band frequencies, may be within FR2, ormay be within the EHF band.

The wireless communications system 100 may also operate in a super highfrequency (SHF) region using frequency bands from 3 GHz to 30 GHz, alsoknown as the centimeter band, or in an extremely high frequency (EHF)region of the spectrum (e.g., from 30 GHz to 300 GHz), also known as themillimeter band. In some examples, the wireless communications system100 may support millimeter wave (mmW) communications between UEs 115 andbase stations 105, and EHF antennas of the respective devices may besmaller and more closely spaced than UHF antennas. In some cases, thismay facilitate use of antenna arrays within a device. The propagation ofEHF transmissions, however, may be subject to even greater atmosphericattenuation and shorter range than SHF or UHF transmissions. Techniquesdisclosed herein may be employed across transmissions that use one ormore different frequency regions, and designated use of bands acrossthese frequency regions may differ by country or regulating body.

The wireless communications system 100 may utilize both licensed andunlicensed radio frequency spectrum bands. For example, the wirelesscommunications system 100 may employ License Assisted Access (LAA),LTE-Unlicensed (LTE-U) radio access technology, or NR technology in anunlicensed band such as the 5 GHz industrial, scientific, and medical(ISM) band. When operating in unlicensed radio frequency spectrum bands,devices such as base stations 105 and UEs 115 may employ carrier sensingfor collision detection and avoidance. In some cases, operations inunlicensed bands may be based on a carrier aggregation configuration inconjunction with component carriers operating in a licensed band (e.g.,LAA). Operations in unlicensed spectrum may include downlinktransmissions, uplink transmissions, P2P transmissions, D2Dtransmissions, or the like.

A base station 105 or UE 115 may be equipped with multiple antennas,which may be used to employ techniques such as transmit diversity,receive diversity, multiple-input multiple-output (MIMO) communications,or beamforming. The antennas of a base station 105 or UE 115 may belocated within one or more antenna arrays or antenna panels, which maysupport MIMO operations or transmit or receive beamforming. For example,one or more base station antennas or antenna arrays may be co-located atan antenna assembly, such as an antenna tower. In some cases, antennasor antenna arrays associated with a base station 105 may be located indiverse geographic locations. A base station 105 may have an antennaarray with a number of rows and columns of antenna ports that the basestation 105 may use to support beamforming of communications with a UE115. Likewise, a UE 115 may have one or more antenna arrays that maysupport various MIMO or beamforming operations. Additionally oralternatively, an antenna panel may support radio frequency beamformingfor a signal transmitted via an antenna port.

Base stations 105 or UEs 115 may use MIMO communications to exploitmultipath signal propagation and increase the spectral efficiency bytransmitting or receiving multiple signals via different spatial layers.Such techniques may be referred to as spatial multiplexing. The multiplesignals may, for example, be transmitted by the transmitting device viadifferent antennas or different combinations of antennas. Likewise, themultiple signals may be received by the receiving device via differentantennas or different combinations of antennas. Each of the multiplesignals may be referred to as a separate spatial stream and may carrybits associated with the same data stream (e.g., the same codeword) ordifferent data streams (e.g., different codewords). Different spatiallayers may be associated with different antenna ports used for channelmeasurement and reporting. MIMO techniques include single-user MIMO(SU-MIMO), where multiple spatial layers are transmitted to the samereceiving device, and multiple-user MIMO (MU-MIMO), where multiplespatial layers are transmitted to multiple devices.

Beamforming, which may also be referred to as spatial filtering,directional transmission, or directional reception, is a signalprocessing technique that may be used at a transmitting device or areceiving device (e.g., a base station 105 or a UE 115) to shape orsteer an antenna beam (e.g., a transmit beam, a receive beam) along aspatial path between the transmitting device and the receiving device.Beamforming may be achieved by combining the signals communicated viaantenna elements of an antenna array such that some signals propagatingat particular orientations with respect to an antenna array experienceconstructive interference while others experience destructiveinterference. The adjustment of signals communicated via the antennaelements may include a transmitting device or a receiving deviceapplying amplitude offsets, phase offsets, or both to signals carriedvia the antenna elements associated with the device. The adjustmentsassociated with each of the antenna elements may be defined by abeamforming weight set associated with a particular orientation (e.g.,with respect to the antenna array of the transmitting device orreceiving device, or with respect to some other orientation).

A base station 105 or UE 115 may use beam sweeping techniques as part ofbeam forming operations. For example, a base station 105 may usemultiple antennas or antenna arrays (e.g., antenna panels) to conductbeamforming operations for directional communications with a UE 115.Some signals (e.g., synchronization signals, reference signals, beamselection signals, or other control signals) may be transmitted by abase station 105 multiple times in different directions. For example,the base station 105 may transmit a signal according to differentbeamforming weight sets associated with different directions oftransmission. Transmissions in different beam directions may be used toidentify (e.g., by a transmitting device, such as a base station 105, ora receiving device, such as a UE 115) a beam direction for subsequenttransmission and/or reception by the base station 105.

Some signals, such as data signals associated with a particularreceiving device, may be transmitted by a base station 105 in a singlebeam direction (e.g., a direction associated with the receiving device,such as a UE 115). In some examples, the beam direction associated withtransmissions along a single beam direction may be determined based on asignal that was transmitted in different beam directions. For example, aUE 115 may receive one or more of the signals transmitted by the basestation 105 in different directions and the UE 115 may report to thebase station 105 an indication of the signal that the UE 115 receivedwith a highest signal quality, or an otherwise acceptable signalquality.

In some cases, transmissions by a device (e.g., by a base station 105 orUE 115) may be performed using multiple beam directions, and the devicemay use a combination of digital precoding or radio frequencybeamforming to generate a combined beam for transmission (e.g., from abase station 105 to a UE 115). The UE 115 may report feedback thatindicates precoding weights for one or more beam directions, and thefeedback may correspond to a configured number of beams across a systembandwidth or one or more sub-bands. The base station 105 may transmit areference signal (e.g., a cell-specific reference signal (CRS), achannel state information reference signal (CSI-RS)), which may beprecoded or unprecoded. The UE 115 may provide feedback for beamselection, which may be a precoding matrix indicator (PMI) orcodebook-based feedback (e.g., a multi-panel type codebook, a linearcombination type codebook, a port selection type codebook). Althoughthese techniques are described with reference to signals transmitted inone or more directions by a base station 105, a UE 115 may employsimilar techniques for transmitting signals multiple times in differentdirections (e.g., for identifying a beam direction for subsequenttransmission or reception by the UE 115) or for transmitting a signal ina single direction (e.g., for transmitting data to a receiving device).

A receiving device (e.g., a UE 115) may try multiple receiveconfigurations (e.g., directional listening) when receiving varioussignals from the base station 105, such as synchronization signals,reference signals, beam selection signals, or other control signals. Forexample, a receiving device may try multiple receive directions byreceiving via different antenna subarrays, by processing receivedsignals according to different antenna subarrays, by receiving accordingto different receive beamforming weight sets (e.g., differentdirectional listening weight sets) applied to signals received atmultiple antenna elements of an antenna array, or by processing receivedsignals according to different receive beamforming weight sets appliedto signals received at multiple antenna elements of an antenna array,any of which may be referred to as “listening” according to differentreceive configurations or receive directions. In some examples, areceiving device may use a single receive configuration to receive alonga single beam direction (e.g., when receiving a data signal). The singlereceive configuration may be aligned in a beam direction determinedbased on listening according to different receive configurationdirections (e.g., a beam direction determined to have a highest signalstrength, highest signal-to-noise ratio (SNR), or otherwise acceptablesignal quality based on listening according to multiple beamdirections).

The wireless communications system 100 may be a packet-based networkthat operates according to a layered protocol stack. In the user plane,communications at the bearer or Packet Data Convergence Protocol (PDCP)layer may be IP-based. A Radio Link Control (RLC) layer may performpacket segmentation and reassembly to communicate over logical channels.A MAC layer may perform priority handling and multiplexing of logicalchannels into transport channels. The MAC layer may also use errordetection techniques, error correction techniques, or both to supportretransmissions at the MAC layer to improve link efficiency. In thecontrol plane, the RRC protocol layer may provide establishment,configuration, and maintenance of an RRC connection between a UE 115 anda base station 105 or core network 130 supporting radio bearers for userplane data. At the Physical layer, transport channels may be mapped tophysical channels.

UEs 115 and base stations 105 may support retransmissions of data toincrease the likelihood that data is received successfully. Hybridautomatic repeat request (HARQ) feedback is one technique for increasingthe likelihood that data is received correctly over a communication link125. HARQ may include a combination of error detection (e.g., using acyclic redundancy check (CRC)), forward error correction (FEC), andretransmission (e.g., automatic repeat request (ARQ)). HARQ may improvethroughput at the MAC layer in poor radio conditions (e.g., lowsignal-to-noise conditions). In some cases, a device may supportsame-slot HARQ feedback, where the device may provide HARQ feedback in aspecific slot for data received in a previous symbol in the slot. Inother cases, the device may provide HARQ feedback in a subsequent slot,or according to some other time interval.

In some cases, a UE 115 may monitor a communication link 125 (e.g., awireless link) 115 continuously for an indication that the UE 115 mayreceive data. In other cases (e.g., to conserve power and extend batterylife) a UE 115 may be configured with a DRX cycle. A DRX cycle includesan “On Duration” when the UE 115 may monitor for control information(e.g., on a physical downlink control channel (PDCCH)) and a “DRXperiod” when the UE 115 may power down radio components. In some cases,a UE 115 may be configured with a short DRX cycle and a long DRX cycle.In some cases, a UE 115 may enter a long DRX cycle if it is inactive forone or more short DRX cycles. The transition between the short DRXcycle, the long DRX cycle and continuous reception may be controlled byan internal timer or by messaging from a base station 105. A UE 115 mayreceive scheduling messages on PDCCH during the ON Duration. Whilemonitoring PDCCH for a scheduling message, the UE 115 may initiate a“DRX Inactivity Timer”. If a scheduling message is successfullyreceived, the UE 115 may prepare to receive data and the DRX InactivityTimer may be reset. When the DRX Inactivity Timer expires withoutreceiving a scheduling message, the UE 115 may move into a short DRXcycle and may start a “DRX Short Cycle Timer”. When the DRX Short CycleTimer expires, the UE 115 may resume a long DRX cycle.

Wireless communications system 100 may support various techniques forpower savings when communicating on a sidelink. As an example, a UE 115may determine one or more sidelink DRX parameters for use whencommunicating with another UE 115 over a sidelink communication link.The sidelink DRX parameters may be indicated to the UE 115 by a basestation 105 or by another UE 115 (e.g., an in-coverage UE 115). In someexamples, a UE 115 may select the sidelink DRX parameters from a set ofsidelink DRX parameters, and the UE 115 may indicate the selectedparameters to another UE 115 (e.g., an out-of-coverage UE 115). Based onthe sidelink DRX parameters received, a UE 115 may discontinuouslymonitor for transmissions from another UE 115 over the sidelinkcommunication link. As such, the UE 115 may refrain from continuouslymonitoring for sidelink transmissions in accordance with the sidelinkDRX parameters (e.g., an ON duration, various sidelink DRX timers, andother DRX parameters), and the UE 115 may thereby save power and reducebattery consumption at the UE 115.

Wireless communications system 100 may further support the separateconfiguration of DRX cycles. For instance, a sidelink DRX configurationmay be different from a DRX configuration used for communications with abase station 105 (e.g., corresponding to a Uu interface). The separateconfigurations may be based on a CC or multiple CCs used for thesidelink and the access link (e.g., communication link 125), or may bebased on a PLMN RF spectrum band used for the sidelink and access link,or based on other communication schemes for sidelink and access linktransmissions, or any combination thereof. Here, the separateconfigurations of DRX cycles may enable a UE 115 to power downrespective power amplifiers used for sidelink and access linktransmissions, thereby providing a configurable and dynamic powersavings at the device.

In other examples described herein, a sidelink DRX configuration may besimilar to or the same as a DRX configuration corresponding to the Uuinterface. In such cases, parameters for the respective DRX cycles mayenable an alignment of the timing for both monitoring for communicationsfrom a base station 105 and monitoring for communications from a UE 115.For example, there may be a synchronization of access link and sidelinkDRX periods, where an in-coverage UE 115 (e.g., acting as a relay forone or more other UEs 115) may use a UE-specific DRX configurationhaving some common periodicity or monitoring occasion(s) between asidelink DRX cycle and other DRX cycles. In some cases, such a relay UE115 may periodically monitor for transmissions (e.g., includingscheduling requests, or other requests to connect to a base station 105)with a certain periodicity from an out-of-coverage UE 115, while theout-of-coverage UE 115 may, in some cases, monitor for transmissionsfrom the relay UE 115 with a different periodicity. In some examples,DRX configurations may be resource-specific, where different sidelinkresources may be associated with respective DRX parameters (e.g., whereUEs 115 may be indicated a DRX configuration on a per-resource basis).

One or more of the base stations 105 may include a base stationcommunications manager 101, which may configure one or more sidelink DRXparameters for sidelink communication between a first UE 115 and asecond UE 115 over a sidelink communication link 135 and transmit, tothe first UE 115, a message indicating the one or more sidelink DRXparameters. The base station communications manager 101 may be anexample of aspects of the base station communications manager 1210described herein.

UEs 115 may include a UE communications manager 102-a, which maydetermine one or more sidelink DRX parameters for sidelink communicationwith a second UE and transmit, to the second UE 115 associated with asecond communications manager 102-b, an indication of the one or moresidelink DRX parameters, where the indication is transmitted over asidelink communication link 135 with the second UE 115. The UEcommunications manager 102-a may also determine one or more sidelink DRXparameters for sidelink communication with a second UE 115 and secondcommunications manager 102-b and discontinuously monitor a sidelinkcommunication link 135 for a transmission from the second UE 115 inaccordance with the one or more sidelink DRX parameters. The UEcommunications managers 102 may examples of aspects of the UEcommunications manager 810 described herein.

FIG. 2 illustrate examples of wireless communications systems 200-a,200-b, and 200-c that support power saving techniques for sidelinkcommunication in accordance with one or more aspects of the presentdisclosure. In some examples, wireless communications systems 200-a,200-b, and 200-c may implement aspects of wireless communications system100. For example, wireless communications systems 200-a, 200-b, and200-c each include a base station 105 (e.g., base station 105-a, basestation 105-b, and base station 105-c) and one or more UEs 115 (e.g.,UEs 115-a through UE 115-f), which may be examples of the correspondingdevices described with reference to FIG. 1 . Wireless communicationssystem 200-a, 200-b, and 200-c may illustrate various levels of coveragefor UEs 115 that communicate using sidelink communications.

In some cases, a UE 115-a may communicate directly with another UE 115-b(or with another group of UEs 115) over a sidelink connection (e.g.,using a peer-to-peer (P2P) or D2D protocol). Such communications may bereferred to as D2D or sidelink communications, where a first UE 115 maybe scheduled (e.g., by a base station 105 or another UE 115) to transmitdata or control information to a second UE 115 over a sidelink. In somecases, a sidelink may be a communication link or a signal transmittedbetween different UEs 115 in a network, where one UE 115 may act as arelay for information transmitted by another device.

In the example of the wireless communications system 200-a, one or moreof a group of UEs 115 (e.g., UE 115-a and UE 115-b) may support sidelinkcommunications in addition to direct communication with a base station105-a within the coverage area 110 of base station 105-a. In such cases,the UEs 115-a and 115-b may be in-coverage. For example, UE 115-a maycommunicate with the base station 105-a via communication link 225-a,while maintaining sidelink communications over sidelink 230-a with theUE 115-b. In addition, UE 115-b may communicate with the base stationover communication link 225-b while communicating with UE 115-a usingthe sidelink 230-a. In some in-coverage cases, each UE 115 may beconnected to the base station 105 via a direct link (e.g., via a Uuinterface).

In the example of wireless communications system 200-b, one or more of agroup of UEs 115 (e.g., UE 115-c and 115-d) may support sidelinkcommunication techniques. In the example of FIG. 2B, UE 115-c may bewithin the coverage area 110 of the base station 105-b, and UE 115-c maycommunicate directly with the base station 105-b using the communicationlink 225-c. Additionally, UE 115-d may be outside of the coverage area110, and may communicate using non-direct links with the base station105-b (e.g., UE 115-d may not have an established Uu or RRC connectionwith base station 105-b). In other cases, the UE 115-d may be inside thecoverage area 110, but may not be able to communicate directly with thebases station 105-b (e.g., the UE 115-d may experience interference,reduced signal strength, or otherwise impeded communications). In suchcases, the UE 115-d may communicate with the UE 115-c using the sidelink230-b.

In the example of FIG. 2B, the group of UEs 115 may be in partialcoverage (e.g., at least one of the UEs may communicate directly withthe base station, and at least one other UE may be out of coverage). Insuch partial-coverage cases, the UE 115 that is in direct communicationwith the base station (e.g., UE 115-c) may act as a relay forinformation transmitted from the base station 105-b. For example, the UE115-c may receive data or control information directly from the basestation 105-b via communication link 225-c, and may relay theinformation via sidelink 230-b to the UE 115-d. In such cases, the UE115-c may assist communications between the base station 105-b and theout of coverage UE 115-d.

In the example of wireless communications system 200-c, one or more of agroup of UEs 115 (e.g., UE 115-e and 115-f) may communicate outside ofthe coverage area 110 of the base station 105-b using a sidelink. Insome examples, the UE 115-e and the UE 115-f may not have a directconnection to the base station 105-c due to both UEs 115 being outsideof the geographic coverage area 110 of base station 105-c. In some otherexamples, the UEs 115 may be inside the geographic coverage area, butmay not be able to communicate directly with the base station 105-c(e.g., due to interference, diminished signal strength, etc.). In suchcases, the UEs 115 may be out of coverage, and may not have a Uuconnection or other direct connection established with the base station105-c.

UE 115-e may be able to communicate directly with another UE 115-f (orwith another group of UEs 115) over the sidelink 230-c. In suchcommunications, the UEs 115 may communicate without direct connection tothe base station 105-c. However, as illustrated in wirelesscommunications systems 200-a, 200-b, and 200-c, there may be cases inwhich a UE 115 is outside the coverage of a base station 105 andtherefore may lack a direct, (e.g., RRC) connection with the networkwhile communicating with another UE 115 via one or more sidelinks 230.Such out-of-coverage UEs 115 may not regularly monitor for pagingsignals from a network, and the out-of-coverage UEs 115 may also beunaware of when other UEs 115 will be transmitting via a sidelinkcommunications link. The out-of-coverage UE 115 and in-coverage UE 115may monitor sidelink resources (e.g., resource pools) for transmissionsfrom other UEs 115. Such monitoring may be continuous, and theout-of-coverage UE 115 may unnecessarily consume power as a result.

As described herein, techniques may be used to enable power saving at adevice communicating via a sidelink 230. As an example, DRX parametersfor sidelink communications may be configured for out-of-coverage UEs115. The sidelink DRX parameters may be configured by a base station 105and transmitted to an out-of-coverage UE 115 via another UE 115 (e.g.,that is in coverage and communicating, via a sidelink communicationslink, with the out-of-coverage UE 115). Additionally or alternatively,the in-coverage UE 115 may select the sidelink DRX parameters and the UE115 may signal the parameters to the out-of-coverage UE 115. As such,the out-of-coverage UE 115 may perform DRX for sidelink communicationsto enable power saving. Further techniques for power saving may includethe separate configuration of DRX parameters (e.g., DRX for thein-coverage UE 115 and a base station 105 over the Uu interface) and thesidelink DRX parameters. Alternatively, the parameters for therespective DRX configurations may be the same.

FIGS. 3A, 3B, and 3C illustrate an example of wireless communicationssystems 300-a, 300-b, and 300-c that support power saving techniques forsidelink communication in accordance with one or more aspects of thepresent disclosure. In some examples, wireless communications systems300-a, 300-b, and 300-c may implement aspects of wireless communicationssystems 100 and 200. For example, wireless communications system 300-a,300-b, and 300-c each include a base station 105-d and one or more UEs115 (e.g., UEs 115-g and UE 115-g), which may be examples of thecorresponding devices described with reference to FIGS. 1 and 2 .Wireless communications system 300-a, 300-b, and 300-c may illustratethe signaling of DRX parameters to UEs 115.

Resources for sidelink communications may be allocated within thewireless communications system 300-a according to a number of differentresource allocation techniques. In some implementations, sidelinkresources for a PSCCH and a physical sidelink shared channel (PSSCH) maybe scheduled by the base station 105-d. For example, the base station105-d may receive an indication that UE 115-g is to facilitate sidelinkcommunications with a target UE 115-h. In some examples, the target UE115-h may be out of coverage of the base station 105-d. The base stationmay transmit an indication 305 to UE 115-g using communication link 310to indicate resources that the UE 115-g may use to communicate with theUE 115-h. For example, the indication 305 may be DCI transmitted on thePDCCH. The DCI may include a PSCCH period or a set of sidelink slotsthat the UE 115-g may use to transmit data to the UE 115-h. The UE 115-gmay transmit information using the PSCCH and the PSSCH to UE 115-h usingthe indicated resources (e.g., the UE may transmit PSCCH and PSSCHtogether within the indicated PSCCH period).

Additionally or alternatively, the indication 305 transmitted by thebase station 105-d may indicate a set of resource pools (e.g., includinguplink resource pools and downlink resource pools) that the UE 115-g mayuse to transmit information to the UE 115-h. In such examples, the UE115-g may receive DCI which activates one of a set of available resourcepools that the UE 115-g may use. In some other examples, the UE 115-gmay select one resource pool form the set of available resource poolswithout receiving DCI.

After receiving information from the base station 105-d, the UE 115-gmay communicate with the UE 115-h using a sidelink connection 315. Insome aspects, the UE 115-g may act as a relay between base station 105-dand UE 115-h. For example, the UE 115-g may receive an indication ofvarious transmission resources it may use to communicate with the UE115-h according to methods described with reference to FIG. 3A. The UE115-g may select a configured PSCCH/PSSCH period to transmit PSCCH andPSSCH to the UE 115-h in a single slot or a set of slots of thePSCCH/PSSCH period. Additionally or alternatively, the UE 115-g mayselect an available resource pool to use to transmit PSCCH and PSSCH tothe UE 115-h (e.g., which may be done without instruction or signalingfrom the base station 105-d). After resource allocation, the UE 115-gmay transmit data to the UE 115-h using the configured resources.

In some aspects, the PSCCH transmitted by UE 115-g to the target UE115-h during sidelink communications may be analogous to a PDCCH whichmay be transmitted from the base station 105-d to the UE 115-g duringinitial communications described with reference to FIG. 3A. In addition,a PSSCH which may be transmitted by the UE 115-g to the UE 115-h duringsidelink communication may be analogous to a physical downlink sharedchannel (PDSCH) or a physical uplink shared channel (PUSCH) which may betransmitted by the base station 105-d or a UE 115, respectively.

In some cases, UEs 115 within a network may be configured to monitor acontrol channel discontinuously in order to increase power savings. Forexample, the UEs 115 may implement sidelink DRX methods which may allowa UE 115 to turn off its receiver, power amplifier, and/or othercomponents of an RF chain during periods of inactivity, and turn on itsreceiver or RF chain components during times where the UE 115 may beconfigured to receive data on a sidelink. In such cases, a UE 115 may beconfigured with a sidelink DRX cycle, which may indicate various timeperiods or a periodicity at which the UE 115 may monitor a controlchannel. For example, UEs 115 within the network may use a configuredsidelink DRX cycle to monitor PDCCH for communications with a basestation 105, and UEs 115 may also use a configured sidelink DRX cycle tomonitor PSCCH for sidelink communications.

In one example, base station 105-d may configure a sidelink DRXconfiguration for a number of UEs 115. In some other examples, however,a UE 115 that is out of coverage (e.g., UE 115-h) may receive anindication of a sidelink DRX configuration via sidelink communicationswith another UE 115 that is in coverage (e.g., UE 115-g). A sidelink DRXconfiguration may be indicated to the receiving UE 115 (e.g., UE 115-h)according to different aspects of communications established within thenetwork.

In some cases, the UE 115-h may be out-of-coverage (e.g., UE 115-h maynot be Uu connected, and UE 115-h may not have an RRC connection withbase station 105-d). As a result, the UE 115-h may not monitor forpaging information from the base station 105-d, (e.g., as it mayotherwise perform according to an RRC idle mode). In such cases, asidelink DRX configuration may be indicated or relayed to the UE 115-hby another UE 115, for example, by UE 115-g.

There may be a number of different ways in which the sidelink DRXconfiguration may be selected for the UE 115-h. In one implementation,the base station 105-d may select the sidelink DRX parameters for the UE115-h. This implementation may, in some aspects, be used forpartial-coverage scenarios (e.g., where at least one UE 115 is incoverage of the base station 105-d). The base station 105-d may receivean indication that a source UE 115 (e.g., UE 115-g) may communicate withone or multiple out of coverage UEs 115 present in the network. The basestation 105-d may then select parameters for a sidelink DRXconfiguration for the out of coverage UEs, and the base station 105-dmay transmit the sidelink DRX parameters to the source UE 115-g. In somecases, the base station 105-d may transmit the sidelink DRX parameterson a PDSCH according to the signaling described with reference to FIG.3A (e.g., via indication 305). The UE 115-g may receive the sidelink DRXparameters from the base station 105-d, and UE 115-g may transmit orrelay the sidelink DRX parameters via a sidelink (e.g., via PSSCH) tothe UE 115-h according to the signaling described with respect to FIG.3B.

In another implementation, sidelink DRX parameters for UE 115-h may beselected by the UE 115-g (e.g., without direct communication from thebase station). In such implementations, the source UE 115-g may select asidelink DRX cycle based on its own DRX cycle (this DRX cycle may beconfigured by the base station 105-d). In addition, the source UE 115-gmay select sidelink DRX parameters that are compatible with values ofits own DRX cycle or wake up durations. The UE 115-g may relay thesesidelink DRX parameters to UE 115-h, or to various other out of coverageUEs. In some other cases, the target UE 115-h may be in coverage of thebase station 105-d, but may still receive a DRX configuration from thesource UE 115-g.

Implementations in which a UE may configure a sidelink DRX configurationfor another UE 115 may be used, for example, in partial coveragescenarios, or for out of coverage scenarios with an establishedmaster-slave architecture. In examples where all of the UEs are out ofcoverage, a master-slave architecture may be implemented where one UE115 is designated as a master (e.g., a source UE 115 such as UE 115-gmay be a master), and other UEs 115 may be designated as slaves (e.g., atarget UE 115 such as UE 115-h may be a slave). In this case, the masterUE 115 may be a central entity in the group, and UE 115 may pick varioussidelink DRX configuration parameters that it may transmit to the otherUEs 115 in the group.

The source UE 115-g may send the sidelink DRX parameters to the targetUE 115-h using various signaling techniques. In one example, the sourceUE 115-g may send the sidelink DRX parameters over a sidelink connectionusing a MAC CE of a PSSCH. Additionally or alternatively, the sidelinkDRX parameters may be indicated in SCI (e.g., the target UE 115-h mayreceive a DCI via the PSCCH from transmitted from the target UE 115-g).The target UE 115-h (or in some cases, group of target UEs) may beassociated with a destination identity (ID) (or group destination ID).The source UE 115-g may transmit the destination ID in addition thesidelink DRX configuration, and based on the destination ID, the targetUE 115-h may determine if it may receive the transmitted message. Insome cases, the destination ID may include a groupcast destination ID ora unicast destination ID. Additionally, as part of a configuration ofsidelink resource pools (e.g., resource pools used for receiving andtransmitting sidelink communications), the sidelink DRX parameters mayalso be configured (e.g., as part of a resource pool configuration). Assuch, if some UEs are out of coverage, the UEs may determine when tomonitor for sidelink transmissions based on the DRX parameters includedwithin a resource pool configuration.

In some examples, a MAC entity may be configured by RRC with sidelinkDRX functionality that may in some aspects control PDCCH or PSCCHmonitoring activity at a UE 115 (e.g., UE 115-g) for the various radionetwork temporary identifier (RNTI) configurations of the MAC entity.For example, some RNTI configurations may include C-RNTI, CS-RNTI,INT-RNTI, SFI-RNTI, SP-CSI-RNTI, PRC-PUCCH-RNTI, and TPC-SRS-RNTI. Insome cases where the UE 115 is in RRC Connected mode and configured forDRX, the MAC entity may monitor the PDCCH discontinuously (e.g., usingvarious ON occasions and an OFF occasions) for each serving cell. Insome other cases where the UE is in an RRC Idle mode, the UE 115 maymonitor paging occasions transmitted by the base station, and UE 115 maymonitor the PDCCH to detect a paging message. If the UE 115-g receives apaging message, it may wake up, but if it does not receive a pagingmessage, it may remain in an idle mode.

A number of different parameters may be considered in determining thesidelink DRX configuration for a UE 115. Some DRX parameters (e.g.,given by RRC) may include, for example, a drx-onDurationTimer, which mayindicate the duration at the beginning of a DRX Cycle and adrx-SlotOffset which may indicate the delay before starting thedrx-onDurationTimer. Further parameters may include adrx-InactivityTimer to indicate the duration after the PDCCH occasion inwhich a PDCCH indicates a new uplink or downlink transmission for theMAC entity, a drx-LongCycleStartOffset which may indicate the Long DRXcycle, and drx-StartOffset which defines the subframe where the Long andShort DRX Cycle starts. A drx-ShortCycle may be included to indicate theShort DRX cycle, and a drxShortCycleTimer may be included to indicatethe duration that the UE 115 may follow the Short DRX cycle. It is alsonoted that additional or different DRX parameters other than thosedescribed herein may be used for a sidelink DRX configuration and areomitted for the sake of brevity.

The UE 115-h may receive an indication of various sidelink DRXconfigurations via a sidelink connection with UE 115-g. In a firstexample of a DRX configuration, a sidelink DRX configuration 320 mayinclude a number of ON and OFF durations according to a configuredperiodicity. The sidelink DRX configuration may include an ON durationof a given length 325, and an OFF duration of a given length (e.g., theOFF duration may have the same duration as the ON duration). A sidelinkDRX cycle 330 may be defined by a time period that passes during one ONduration and one OFF duration. The sidelink DRX configuration 320 mayindicate the times at which a UE monitors a control channel, forexample, the UE 115-h may monitor the PSCCH during ON durations 325.

In some cases, a sidelink DRX configuration (e.g., sidelink DRXconfiguration 335) may include an inactivity timer associated with thereception of a control channel signal. The sidelink DRX configuration335 may include a number of ON and OFF durations according to aconfigured periodicity, and the sidelink DRX cycle 330 may be a timeperiod that passes during the completion of one ON duration and one OFFduration. During and ON duration 325, the UE 115-h may receive a PSCCHat 340. After receiving the PSCCH, the ON duration (where the PSCCH wasreceived) may be extended by an amount 345, which may be configured bythe inactivity timer. In some cases, the inactivity timer may extend theOFF duration to be longer than the ON duration 325 (e.g., longer thanthe ON duration if no PSCCH is received). In some cases, the inactivitytimer may indicate that the ON duration may be extended for a givenamount of time, for example, in order for the UE 115-h to receive data.After the inactivity timer expires, the UE 115-h may return to a sleepor idle state, and may continue to wake up periodically to monitor PSCCHaccording to the sidelink DRX configuration 335.

In some implementations, long and short DRX cycles may be included insidelink DRX configuration 350. In one example, UE 115-h may detect aPSCCH at 355 at the beginning of the sidelink DRX cycle. The PSCCH mayinitiate an inactivity timer, which may span the duration 360, and theinactivity timer may remain on for an amount of time after the UEreceives the PSCCH. After the inactivity timer completes, a shortsidelink DRX cycle may be configured (e.g., the DRX cycle duration 370for the short DRX cycle may be shorter than a threshold DRX cyclelength). Additionally, a drxShortCycleTimer may be configured to spanthe time period 375, which may include a number of short DRX cycles 370.After the expiration of the sidelink DRX short cycle timer (and in thecase where the UE does not receive PSCCH during the sidelink DRX shortcycle time period 375), a long DRX cycle may be configured (e.g., thesidelink DRX cycle duration 385 for the long sidelink DRX cycle may belonger than a threshold sidelink DRX cycle duration). After thecompletion of the long sidelink DRX cycle, (and in cases where the UEdoes not receive PSCCH during the long DRX cycle), the UE 115-h, maypower down one or more components of an RF chain, or may otherwisereturn to an idle mode.

FIG. 4 illustrates an example of various DRX configurations 400 thatthat support DRX configurations for sidelink in accordance with one ormore aspects of the present disclosure. In some examples, the DRXconfigurations 400 may implement aspects of wireless communicationssystems 100, 200, and 300.

In some cases, a UE 115 may be configured with multiple DRXconfigurations. For example, a UE may be configured with a DRXconfiguration from a base station and a sidelink DRX configuration. If aUE 115 (for example, a source UE 115 that may relay uplink and downlinktransmissions for out of coverage UEs 115) is in coverage (e.g., has aUu connection), the UE 115 may be configured with a DRX from the basestation 105. Additionally or alternatively, the UE 115 may be configuredwith both the sidelink DRX and the Uu DRX.

In some examples, the DRX configurations (e.g., the sidelink DRX and UuDRX configurations) may be configured separately, such that the DRXparameters may be separate for the different configurations. Forexample, if the Uu link and the sidelink may be established on differentcarriers (e.g., on different inter-band CCs). Additionally oralternatively, the Uu and sidelinks may be on different frequency ranges(e.g., Uu on FR1 and sidelink FR2), and DRX for Uu and the sidelink maybe configured separately. In some other cases, the UE 115 may transmitsidelink communications according to a first operator's (PLMN) band, butmay receive sidelink in another PLMN's band. In such cases, Uu andsidelink DRX may be configured separately.

In addition, there may be cases where one UE 115 associated with onenetwork (e.g., PLMN X) may transmit/receive sidelink in another network(e.g., PLMN Y). In such cases, one operator may transmit or receivesidelink communications in another operator's band. In one example, afirst UE may be associated with one operator and a second UE may beassociated with another operator. Then, for various operations (e.g.,for gaming or other device operations) the first UE and the second UEmay set up a sidelink such that one of the users may roam in otheroperator's band (e.g., for transmissions and/or reception of a sidelinkcommunication). This way, the first UE and the second UE configured withdifferent operators may still utilize the same band. In this case, DRXmay be configured differently for sidelink and Uu.

In some implementations, the component carriers (CCs) associated witheach UE are connected to different power amplifiers (PAs) and likely todifferent RF chains. Therefore, in cases where different DRXconfigurations are configured based on separate links, one or both ofthe RF chains may be turned off. Stated alternatively, there are caseswhere all of the CCs are connected to one RF chain, such that if one UE115 is woken up, all of the UEs associated with that RF chain may alsobe woken up. However, if multiple UEs are associated with different RFchains, and a CC associated with one RF chain is woken up, a differentCC associated with another RF chain may remain idle (e.g., in cases forcommunications on FR1 and FR2, or for the case of inter-band CC). Thismay reduce the number of blind decodes performed by the UE 115 because aselect number of CCs may be monitored, which may increase power savings.

There may be some cases where sidelink and Uu BWPs are on the samecarrier. In such cases, DRX configurations between sidelink and Uu maybe different. The base station still may have the option to make the DRXconfigurations the same, however, the configurations may also be keptseparate. In some cases, the configuration signaling for sidelink BWPsmay be separate from the configuration signaling for uplink BWPs. Insuch cases, a UE 115 may not be expected to use different numerologiesin a configured sidelink BWP and an active uplink BWP in the samecarrier at a given time. In some cases, the BWP may be defined forsidelink. In a licensed carrier, the sidelink BWP may be definedseparately from the uplink BWP or defined relative to the uplink BWP.

In another example, the DRX configurations may be kept separate, becauseidentical DRX configurations may be based on the tightest requirementsof Uu and sidelink.

FIG. 4 illustrates an example of various DRX configurations 400. Thesidelink DRX configuration 401 may have an ON duration according to timeperiod 405-a, and a DRX cycle duration of 410-a. The sidelink DRXconfiguration 401 may be a configuration that a UE 115 may communicatevia a sidelink to another UE 115 within the network. The Uu DRXconfiguration 402 may similarly include an ON duration according to thetime period 415, and a DRX cycle duration of 420. In some examples, suchas the example described with reference to FIG. 4 , the DRX cycleduration associated with the Uu DRX configuration 402 may be greaterthan the DRX cycle duration associated with the sidelink DRXconfiguration 401.

In cases where DRX configurations may not be kept separate for differentUEs 115, the base station 105 or source UE 115 may select a DRX cycleassociated with the greatest number of ON durations (e.g., the sync DRXconfiguration). In cases where the UE 115 selects the synchronized DRXconfiguration 403, the UE 115 may monitor more PDCCHs over a largerportion of time.

In cases where the DRX configurations may be kept separate for differentUEs 115, however, the base station 105 or source UE 115 may select a DRXconfiguration with the least number of ON durations (e.g., the leastnumber of monitoring occasions), which may increase power savings andlimit the number of times a target UE 115 may wake up to monitor for acontrol channel transmission. In addition, if the configurations arekept separate, the UE 115 may monitor a smaller number of PDCCHcandidates. For example, for cases where the DRX is configuredseparately for separate devices, the UE 115 may use the sidelink DRXconfiguration 401 for sidelink communications, and the UE 115 may usethe Uu DRX configuration 402 for Uu communications (rather than usingthe sidelink DRX configuration 401 for all communications).

In some cases, a synchronized DRX configuration 403 may be used when aUE 115 is in coverage and configured to relay packets to one or moreremote (e.g., out-of-coverage) UEs 115. In such cases, the relay UE 115may have a UE-specific DRX periodicity. Further, because the relay UE115 may relay transmissions to/from other remote UEs 115, the relay UE115 may utilize a monitoring periodicity that is common to multiple DRXperiods (e.g., using some common denominator or parameter between thetwo or more DRX configurations). In some cases, different remote UEs 115may monitor the relay UE 115 according to different DRX periods (e.g.,different sidelink DRX periods).

The relay UE 115 may periodically monitor for requests (e.g., schedulingrequest-like transmissions) from the one or more out-of-coverage UEs115. As an illustrative example, the relay UE 115 may assist a remote,out-of-coverage UE 115 to connect to a base station 105. The remote UE115 may generate uplink traffic to be relayed to the base station viathe relay UE 115. Similar to examples where the relay UE 115 may monitorfor PDCCH paging from the base station, the relay UE 115 may monitor forsuch requests from the remote UE 115. The monitoring periods may beknown to both the relay UE 115 and remote UEs 115. In some cases, themonitoring periods may be allocated or configured by the base station.In some cases, the base station may signal an indication of themonitoring periods to one or more UEs 115. In some examples, the relayUE 115 may synchronize its monitoring periods with respect to the basestation and remote UE(s) 115, which may provide for efficient monitoringand reduced power consumption at the relay UE 115. Thus, by usingsynchronized DRX configuration 403, a UE 115 may efficiently monitor fortransmissions from a base station and from one or more remote UEs 115,which may facilitate data traffic for the one or more remote UEs 115.

In some cases, there may be multiple resource pool configurations forsidelink transmissions between UEs in a network. In such cases, the DRXparameters may be configured separately for each of the resource pools(e.g., DRX configurations may be allocated per resource pool). In somecases, each UE 115 may be informed about a sidelink DRX configuration ona per-resource pool basis.

FIG. 5 shows a block diagram 500 of a device 505 that supports DRXconfigurations for sidelink in accordance with one or more aspects ofthe present disclosure. The device 505 may be an example of aspects of aUE 115 as described herein. The device 505 may include a receiver 510, aUE communications manager 515, and a transmitter 520. The device 505 mayalso include a processor. Each of these components may be incommunication with one another (e.g., via one or more buses).

The receiver 510 may provide a means for receiving information such aspackets, user data, or control information associated with variousinformation channels (e.g., control channels, data channels, andinformation related to DRX configurations for sidelink, etc.).Information may be passed on to other components of the device 505. Thereceiver 510 may be an example of aspects of the transceiver 820described with reference to FIG. 8 . The receiver 510 may utilize asingle antenna or a set of antennas.

The UE communications manager 515 may be configured to provide orsupport a means for determining one or more sidelink DRX parameters forsidelink communication with a second UE and transmit, to the second UE,an indication of the one or more sidelink DRX parameters, where theindication is transmitted over a sidelink communication link with thesecond UE. The UE communications manager 515 may also be configured toprovide or support a means for determining one or more sidelink DRXparameters for sidelink communication with a second UE anddiscontinuously monitor a sidelink communication link for a transmissionfrom the second UE in accordance with the one or more sidelink DRXparameters. The UE communications manager 515 may be an example ofaspects of the UE communications manager 810 described herein.

The UE communications manager 515 may be an example of means forperforming various aspects of managing DRX configurations for sidelinkas described herein. The communications manager 515, or itssub-components, may be implemented in hardware (e.g., in communicationsmanagement circuitry). The circuitry may comprise of processor, digitalsignal processor (DSP), an application-specific integrated circuit(ASIC), a field programmable gate array (FPGA) or other programmablelogic device, discrete gate or transistor logic, discrete hardwarecomponents, or any combination thereof designed to perform the functionsdescribed in the present disclosure.

In another implementation, the UE communications manager 515, or itssub-components, may be implemented in hardware, code (e.g., ascommunications management software or firmware) executed by a processor,or any combination thereof. If implemented in code executed by aprocessor, the functions of the UE communications manager 515, or itssub-components may be executed by a general-purpose processor, a DSP, anASIC, a FPGA, or other programmable logic device, discrete gate ortransistor logic, discrete hardware components, or any combinationthereof designed to perform the functions described in the presentdisclosure.

In some examples, the UE communication manager 515 may be configured toperform various operations (e.g., determining, transmitting, etc.) usingor otherwise in cooperation with the receiver 510, the transmitter 520,or both.

The UE communications manager 515, or its sub-components, may bephysically located at various positions, including being distributedsuch that portions of functions are implemented at different physicallocations by one or more physical components. In some examples, the UEcommunications manager 515, or its sub-components, may be a separate anddistinct component in accordance with various aspects of the presentdisclosure. In some examples, the UE communications manager 515, or itssub-components, may be combined with one or more other hardwarecomponents, including but not limited to an input/output (I/O)component, a transceiver, a network server, another computing device,one or more other components described in the present disclosure, or acombination thereof in accordance with various aspects of the presentdisclosure.

The transmitter 520 may transmit signals generated by other componentsof the device 505. In some examples, the transmitter 520 may becollocated with a receiver 510 in a transceiver module. For example, thetransmitter 520 may be an example of aspects of the transceiver 820described with reference to FIG. 8 . The transmitter 520 may utilize asingle antenna or a set of antennas.

FIG. 6 shows a block diagram 600 of a device 605 that supports DRXconfigurations for sidelink in accordance with one or more aspects ofthe present disclosure. The device 605 may be an example of aspects of adevice 505, or a UE 115 as described herein. The device 605 may includea receiver 610, a UE communications manager 615, and a transmitter 635.The device 605 may also include a processor. Each of these componentsmay be in communication with one another (e.g., via one or more buses).

The receiver 610 may receive information such as packets, user data, orcontrol information associated with various information channels (e.g.,control channels, data channels, and information related to DRXconfigurations for sidelink, etc.). Information may be passed on toother components of the device 605. The receiver 610 may be an exampleof aspects of the transceiver 820 described with reference to FIG. 8 .The receiver 610 may utilize a single antenna or a set of antennas.

The UE communications manager 615 may be an example of aspects of the UEcommunications manager 515 as described herein. The UE communicationsmanager 615 may include a sidelink DRX component 620, a sidelinkcommunications manager 625, and a monitoring component 630. The UEcommunications manager 615 may be an example of aspects of the UEcommunications manager 810 described herein.

The sidelink DRX component 620 may provide a means for determining oneor more sidelink DRX parameters for sidelink communication with a secondUE.

The sidelink communications manager 625 may provide a means fortransmitting, to the second UE, an indication of the one or moresidelink DRX parameters, where the indication is transmitted over asidelink communication link with the second UE.

The sidelink DRX component 620 may provide a means for determining oneor more sidelink DRX parameters for sidelink communication with a secondUE.

The monitoring component 630 may provide a means for discontinuouslymonitoring a sidelink communication link for a transmission from thesecond UE in accordance with the one or more sidelink DRX parameters.

The transmitter 635 may provide a means for transmitting signalsgenerated by other components of the device 605. In some examples, thetransmitter 635 may be collocated with a receiver 610 in a transceivermodule. For example, the transmitter 635 may be an example of aspects ofthe transceiver 820 described with reference to FIG. 8 . The transmitter635 may utilize a single antenna or a set of antennas.

In some examples, communications manager 615 may be implemented as anintegrated circuit or chipset for a mobile device modem, and thereceiver 610 and transmitter 620 may be implemented as analog components(e.g., amplifiers, filters, antennas, etc.) coupled with the mobiledevice modem to enable wireless transmission and reception.

The communications manager 615 as described herein may be implemented torealize one or more potential advantages. Various implementations mayenable the communications manager 615 to implement a DRX cycle formonitoring for a transmission from another device in the network. Atleast one implementation may enable the communications manager 615 tosupport sidelink communications between devices in accordance with aconfigured DRX cycle.

Based on implementing the power saving techniques as described herein,one or more processors of the device 605 (e.g., processor(s) controllingor incorporated with one or more of receiver 610, communications manager615, and transmitter 620) may reduce the amount of time a device isawake and consuming excess power, which may increase power savings. Inaddition, the processors of the device 605 may be configured to turn offor remain in a low power mode in accordance with the DRX cycle, whichmay reduce excess power consumption at the device 605.

FIG. 7 shows a block diagram 700 of a UE communications manager 705 thatsupports DRX configurations for sidelink in accordance with one or moreaspects of the present disclosure. The UE communications manager 705 maybe an example of aspects of a UE communications manager 515, a UEcommunications manager 615, or a UE communications manager 810 describedherein. The UE communications manager 705 may include a sidelink DRXcomponent 710, a sidelink communications manager 715, a parameterselection component 720, a DRX manager 725, and a monitoring component730. Each of these modules may communicate, directly or indirectly, withone another (e.g., via one or more buses).

The sidelink DRX component 710 may provide a means for determining oneor more sidelink DRX parameters for sidelink communication with a secondUE. In some examples, the sidelink DRX component 710 may provide a meansfor determining one or more sidelink DRX parameters for sidelinkcommunication with a second UE. In some examples, the sidelink DRXcomponent 710 may provide a means for receiving, from a base station, amessage indicating the one or more sidelink DRX parameters for thesecond UE.

In some examples, the sidelink DRX component 710 may provide a means fortransmitting an indication of a destination identity that corresponds toan identity of the second UE, where the one or more sidelink DRXparameters are identified based on the destination identity. In someexamples, the sidelink DRX component 710 may provide a means fortransmitting the indication to the second UE via SCI, or a MAC controlelement, or a combination thereof.

In some examples, the sidelink DRX component 710 may provide a means fortransmitting the DCI to the second UE on a physical sidelink controlchannel. In some examples, the sidelink DRX component 710 may power downa second power amplifier for the sidelink communication link inaccordance with the one or more sidelink DRX parameters. In someexamples, the sidelink DRX component 710 may provide a means forreceiving, from the second UE, an indication of the one or more sidelinkDRX parameters, the indication received over the sidelink communicationlink, where the one or more sidelink DRX parameters are determined basedon the received indication.

In some examples, the sidelink DRX component 710 may provide a means forreceiving the indication of the one or more sidelink DRX parameters fromthe second UE via SCI, or a MAC control element, or a combinationthereof. In some examples, the sidelink DRX component 710 may provide ameans for receiving the DCI from the second UE on a physical sidelinkcontrol channel. In some examples, the sidelink DRX component 710 mayprovide a means for receiving, from a base station, a message indicatingthe one or more sidelink DRX parameters for the second UE, where the oneor more sidelink DRX parameters are determined based on the receivedindication.

In some examples, the sidelink DRX component 710 may provide a means forreceiving the one or more sidelink DRX parameters based on a destinationidentity corresponding to an identity of the first UE, wherediscontinuously monitoring the sidelink communication link is based onidentifying the one or more sidelink DRX parameters. In some cases, theone or more sidelink DRX parameters includes an ON duration, an offsetduration, an inactivity timer, one or more cycle durations, a cycletimer, or any combination thereof.

In some cases, the first UE is within a coverage area of a base station.In some cases, the first UE and the second UE are outside a coveragearea of a base station. In some cases, the one or more sidelink DRXparameters includes an ON duration, an offset duration, an inactivitytimer, one or more cycle durations, a cycle timer, or any combinationthereof. In some cases, the first UE is outside a coverage area of abase station.

The sidelink communications manager 715 may provide a means fortransmitting, to the second UE, an indication of the one or moresidelink DRX parameters, where the indication is transmitted over asidelink communication link with the second UE. In some examples, thesidelink communications manager 715 may provide a means for transmittinga message to the second UE in accordance with the one or more sidelinkDRX parameters.

The monitoring component 730 may provide a means for discontinuouslymonitoring a sidelink communication link for a transmission from thesecond UE in accordance with the one or more sidelink DRX parameters. Insome examples, the monitoring component 730 may provide a means fordiscontinuously monitoring for a transmission from the base station inaccordance with the one or more DRX parameters.

The parameter selection component 720 may provide a means for selectingthe one or more sidelink DRX parameters from a set of sidelink DRXparameters for the second UE.

The DRX manager 725 may provide a means for receiving, from a basestation, an indication of one or more DRX parameters for communicatingwith the base station, where the one or more DRX parameters aredifferent from the one or more sidelink DRX parameters. In someexamples, the DRX manager 725 may provide a means for powering down afirst power amplifier for communicating with the base station inaccordance with the one or more DRX parameters.

In some examples, respective configurations of the one or more DRXparameters and the one or more sidelink DRX parameters are based on afirst carrier for communicating with the base station and a secondcarrier for the sidelink communication link, a first frequency range forcommunicating with the base station and a second frequency range for thesidelink communication link, one or more bands of a primary land mobilenetwork for the sidelink communication link, or a combination thereof.

In some examples, the DRX manager 725 may provide a means for receiving,from a base station, an indication of one or more DRX parameters forcommunicating with the base station, where the one or more DRXparameters are the same as the one or more sidelink DRX parameters. Insome examples, the DRX manager 725 may provide a means fordiscontinuously monitoring for a transmission from the base station inaccordance with the one or more DRX parameters.

FIG. 8 shows a diagram of a system 800 including a device 805 thatsupports DRX configurations for sidelink in accordance with one or moreaspects of the present disclosure. The device 805 may be an example ofor include the components of device 505, device 605, or a UE 115 asdescribed herein. The device 805 may include components forbi-directional voice and data communications including components fortransmitting and receiving communications, including a UE communicationsmanager 810, an I/O controller 815, a transceiver 820, an antenna 825,memory 830, and a processor 840. These components may be in electroniccommunication via one or more buses (e.g., bus 845).

The UE communications manager 810 may be configured to support orprovide a means for determining one or more sidelink DRX parameters forsidelink communication with a second UE and transmit, to the second UE,an indication of the one or more sidelink DRX parameters, where theindication is transmitted over a sidelink communication link with thesecond UE. The UE communications manager 810 may also be configured tosupport or provide a means for determining one or more sidelink DRXparameters for sidelink communication with a second UE anddiscontinuously monitor a sidelink communication link for a transmissionfrom the second UE in accordance with the one or more sidelink DRXparameters.

The I/O controller 815 may manage input and output signals for thedevice 805. The I/O controller 815 may also manage peripherals notintegrated into the device 805. In some cases, the I/O controller 815may represent a physical connection or port to an external peripheral.In some cases, the I/O controller 815 may utilize an operating systemsuch as iOS®, ANDROID®, MS-DOS®, MS-WINDOWS®, OS/2®, UNIX®, LINUX®, oranother known operating system. In other cases, the I/O controller 815may represent or interact with a modem, a keyboard, a mouse, atouchscreen, or a similar device. In some cases, the I/O controller 815may be implemented as part of a processor. In some cases, a user mayinteract with the device 805 via the I/O controller 815 or via hardwarecomponents controlled by the I/O controller 815.

The transceiver 820 may communicate bi-directionally, via one or moreantennas, wired, or wireless links as described herein. For example, thetransceiver 820 may represent a wireless transceiver and may communicatebi-directionally with another wireless transceiver. The transceiver 820may also include a modem to modulate the packets and provide themodulated packets to the antennas for transmission, and to demodulatepackets received from the antennas.

In some cases, the wireless device may include a single antenna 825.However, in some cases the device may have more than one antenna 825,which may be capable of concurrently transmitting or receiving multiplewireless transmissions.

The memory 830 may include random-access memory (RAM) and read-onlymemory (ROM). The memory 830 may store computer-readable,computer-executable code 835 including instructions that, when executed,cause the processor to perform various functions described herein. Insome cases, the memory 830 may contain, among other things, a basicinput/output system (BIOS) which may control basic hardware or softwareoperation such as the interaction with peripheral components or devices.

The processor 840 may include an intelligent hardware device, (e.g., ageneral-purpose processor, a DSP, a CPU, a microcontroller, an ASIC, anFPGA, a programmable logic device, a discrete gate or transistor logiccomponent, a discrete hardware component, or any combination thereof).In some cases, the processor 840 may be configured to operate a memoryarray using a memory controller. In other cases, a memory controller maybe integrated into the processor 840. The processor 840 may beconfigured to execute computer-readable instructions stored in a memory(e.g., the memory 830) to cause the device 805 to perform variousfunctions (e.g., functions or tasks supporting DRX configurations forsidelink).

The code 835 may include instructions to implement aspects of thepresent disclosure, including instructions to support wirelesscommunications. The code 835 may be stored in a non-transitorycomputer-readable medium such as system memory or other type of memory.In some cases, the code 835 may not be directly executable by theprocessor 840 but may cause a computer (e.g., when compiled andexecuted) to perform functions described herein.

FIG. 9 shows a block diagram 900 of a device 905 that supports DRXconfigurations for sidelink in accordance with one or more aspects ofthe present disclosure. The device 905 may be an example of aspects of abase station 105 as described herein. The device 905 may include areceiver 910, a base station communications manager 915, and atransmitter 920. The device 905 may also include a processor. Each ofthese components may be in communication with one another (e.g., via oneor more buses).

The receiver 910 may provide a means for receiving information such aspackets, user data, or control information associated with variousinformation channels (e.g., control channels, data channels, andinformation related to DRX configurations for sidelink, etc.).Information may be passed on to other components of the device 905. Thereceiver 910 may be an example of aspects of the transceiver 1220described with reference to FIG. 12 . The receiver 910 may utilize asingle antenna or a set of antennas.

The base station communications manager 915 may be configured to supportor provide a means for configuring one or more sidelink DRX parametersfor sidelink communication between a first UE and a second UE over asidelink communication link and transmitting, to the first UE, a messageindicating the one or more sidelink DRX parameters. The base stationcommunications manager 915 may be an example of aspects of the basestation communications manager 1210 described herein.

The base station communications manager 915 may be an example of meansfor performing various aspects of managing DRX configurations forsidelink as described herein. The base station communications manager915, or its sub-components, may be implemented in hardware (e.g., incommunications management circuitry). The circuitry may comprise ofprocessor, a DSP, an ASIC, an FPGA, or other programmable logic device,discrete gate or transistor logic, discrete hardware components, or anycombination thereof designed to perform the functions described in thepresent disclosure.

In another implementation, the base station communications manager 915,or its sub-components, may be implemented in hardware, code (e.g.,communications management software or firmware) executed by a processor,or any combination thereof. If implemented in code executed by aprocessor, the functions of the base station communications manager 915,or its sub-components may be executed by a general-purpose processor, aDSP, an ASIC, a FPGA or other programmable logic device, discrete gateor transistor logic, discrete hardware components, or any combinationthereof designed to perform the functions described in the presentdisclosure.

In some examples, the base station communications manager 915 may beconfigured to perform various operations (e.g., determining,transmitting) using or otherwise in cooperation with the receiver 910,the transmitter 920, or both.

The base station communications manager 915, or its sub-components, maybe physically located at various positions, including being distributedsuch that portions of functions are implemented at different physicallocations by one or more physical components. In some examples, the basestation communications manager 915, or its sub-components, may be aseparate and distinct component in accordance with various aspects ofthe present disclosure. In some examples, the base stationcommunications manager 915, or its sub-components, may be combined withone or more other hardware components, including but not limited to aninput/output (I/O) component, a transceiver, a network server, anothercomputing device, one or more other components described in the presentdisclosure, or a combination thereof in accordance with various aspectsof the present disclosure.

The transmitter 920 may provide a means for transmitting signalsgenerated by other components of the device 905. In some examples, thetransmitter 920 may be collocated with a receiver 910 in a transceivermodule. For example, the transmitter 920 may be an example of aspects ofthe transceiver 1220 described with reference to FIG. 12 . Thetransmitter 920 may utilize a single antenna or a set of antennas.

FIG. 10 shows a block diagram 1000 of a device 1005 that supports DRXconfigurations for sidelink in accordance with one or more aspects ofthe present disclosure. The device 1005 may be an example of aspects ofa device 905, or a base station 105 as described herein. The device 1005may include a receiver 1010, a base station communications manager 1015,and a transmitter 1030. The device 1005 may also include a processor.Each of these components may be in communication with one another (e.g.,via one or more buses).

The receiver 1010 may provide a means for receiving information such aspackets, user data, or control information associated with variousinformation channels (e.g., control channels, data channels, andinformation related to DRX configurations for sidelink, etc.).Information may be passed on to other components of the device 1005. Thereceiver 1010 may be an example of aspects of the transceiver 1220described with reference to FIG. 12 . The receiver 1010 may utilize asingle antenna or a set of antennas.

The base station communications manager 1015 may be an example ofaspects of the base station communications manager 915 as describedherein. The base station communications manager 1015 may include asidelink DRX configuration manager 1020 and an indication manager 1025.The base station communications manager 1015 may be an example ofaspects of the base station communications manager 1210 describedherein.

The sidelink DRX configuration manager 1020 may provide a means forconfiguring one or more sidelink DRX parameters for sidelinkcommunication between a first UE and a second UE over a sidelinkcommunication link.

The indication manager 1025 may provide a means for transmitting, to thefirst UE, a message indicating the one or more sidelink DRX parameters.

The transmitter 1030 may provide a means for transmitting signalsgenerated by other components of the device 1005. In some examples, thetransmitter 1030 may be collocated with a receiver 1010 in a transceivermodule. For example, the transmitter 1030 may be an example of aspectsof the transceiver 1220 described with reference to FIG. 12 . Thetransmitter 1030 may utilize a single antenna or a set of antennas.

FIG. 11 shows a block diagram 1100 of a base station communicationsmanager 1105 that supports DRX configurations for sidelink in accordancewith one or more aspects of the present disclosure. The base stationcommunications manager 1105 may be an example of aspects of a basestation communications manager 915, a base station communicationsmanager 1015, or a base station communications manager 1210 describedherein. The base station communications manager 1105 may include asidelink DRX configuration manager 1110, an indication manager 1115, anidentity manager 1120, and a DRX configuration manager 1125. Each ofthese modules may communicate, directly or indirectly, with one another(e.g., via one or more buses).

The sidelink DRX configuration manager 1110 may provide a means forconfiguring one or more sidelink DRX parameters for sidelinkcommunication between a first UE and a second UE over a sidelinkcommunication link. In some cases, the one or more sidelink DRXparameters includes an ON duration, an offset duration, an inactivitytimer, one or more cycle durations, a cycle timer, or any combinationthereof. In some cases, the first UE is within a coverage area of thebase station and the second UE is outside the coverage area of the basestation.

The indication manager 1115 may provide a means for transmitting, to thefirst UE, a message indicating the one or more sidelink DRX parameters.In some examples, the indication manager 1115 may provide a means fortransmitting, to the second UE, a second message indicating the one ormore sidelink DRX parameters. In some examples, the indication manager1115 may provide a means for transmitting, to the first UE, anindication of the one or more DRX parameters.

The identity manager 1120 may provide a means for determining anidentity of the second UE. In some examples, the identity manager 1120may transmit, as part of the message, an indication of a destinationidentity that corresponds to the identity of the second UE, where theone or more sidelink DRX parameters are identified based on thedestination identity.

The DRX configuration manager 1125 may provide a means for configuringone or more DRX parameters for communicating with the first UE, wherethe one or more DRX parameters are different from the one or moresidelink DRX parameters. In some examples, the DRX configuration manager1125 may provide a means for transmitting, to the first UE, anindication of the one or more DRX parameters.

In some examples, respective configurations of the one or more DRXparameters and the one or more sidelink DRX parameters are based on afirst carrier for communicating with the base station and a secondcarrier for the sidelink communication link, a first frequency range forcommunicating with the base station and a second frequency range for thesidelink communication link, one or more bands of a primary land mobilenetwork for the sidelink communication link, or a combination thereof.

In some examples, the DRX configuration manager 1125 may provide a meansfor configuring one or more DRX parameters for communicating with thefirst UE, where the one or more DRX parameters are the same as the oneor more sidelink DRX parameters.

FIG. 12 shows a diagram of a system 1200 including a device 1205 thatsupports DRX configurations for sidelink in accordance with one or moreaspects of the present disclosure. The device 1205 may be an example ofor include the components of device 905, device 1005, or a base station105 as described herein. The device 1205 may include components forbi-directional voice and data communications including components fortransmitting and receiving communications, including a base stationcommunications manager 1210, a network communications manager 1215, atransceiver 1220, an antenna 1225, memory 1230, a processor 1240, and aninter-station communications manager 1245. These components may be inelectronic communication via one or more buses (e.g., bus 1250).

The base station communications manager 1210 may be configured tosupport to provide a means for configuring one or more sidelink DRXparameters for sidelink communication between a first UE and a second UEover a sidelink communication link and transmitting, to the first UE, amessage indicating the one or more sidelink DRX parameters.

The network communications manager 1215 may manage communications withthe core network (e.g., via one or more wired backhaul links). Forexample, the network communications manager 1215 may manage the transferof data communications for client devices, such as one or more UEs 115.

The transceiver 1220 may communicate bi-directionally, via one or moreantennas, wired, or wireless links as described herein. For example, thetransceiver 1220 may represent a wireless transceiver and maycommunicate bi-directionally with another wireless transceiver. Thetransceiver 1220 may also include a modem to modulate the packets andprovide the modulated packets to the antennas for transmission, and todemodulate packets received from the antennas. In some cases, thewireless device may include a single antenna 1225. However, in somecases the device may have more than one antenna 1225, which may becapable of concurrently transmitting or receiving multiple wirelesstransmissions.

The memory 1230 may include RAM, ROM, or a combination thereof. Thememory 1230 may store computer-readable code 1235 including instructionsthat, when executed by a processor (e.g., the processor 1240) cause thedevice to perform various functions described herein. In some cases, thememory 1230 may contain, among other things, a BIOS which may controlbasic hardware or software operation such as the interaction withperipheral components or devices.

The processor 1240 may include an intelligent hardware device, (e.g., ageneral-purpose processor, a DSP, a CPU, a microcontroller, an ASIC, anFPGA, a programmable logic device, a discrete gate or transistor logiccomponent, a discrete hardware component, or any combination thereof).In some cases, the processor 1240 may be configured to operate a memoryarray using a memory controller. In some cases, a memory controller maybe integrated into processor 1240. The processor 1240 may be configuredto execute computer-readable instructions stored in a memory (e.g., thememory 1230) to cause the device 1205 to perform various functions(e.g., functions or tasks supporting DRX configurations for sidelink).

The inter-station communications manager 1245 may manage communicationswith other base station 105, and may include a controller or schedulerfor controlling communications with UEs 115 in cooperation with otherbase stations 105. For example, the inter-station communications manager1245 may coordinate scheduling for transmissions to UEs 115 for variousinterference mitigation techniques such as beamforming or jointtransmission. In some examples, the inter-station communications manager1245 may provide an X2 interface within an LTE/LTE-A wirelesscommunication network technology to provide communication between basestations 105.

The code 1235 may include instructions to implement aspects of thepresent disclosure, including instructions to support wirelesscommunications. The code 1235 may be stored in a non-transitorycomputer-readable medium such as system memory or other type of memory.In some cases, the code 1235 may not be directly executable by theprocessor 1240 but may cause a computer (e.g., when compiled andexecuted) to perform functions described herein.

FIG. 13 shows a flowchart illustrating a method 1300 that supports DRXconfigurations for sidelink in accordance with one or more aspects ofthe present disclosure. The operations of method 1300 may be implementedby a UE 115 (e.g., a first UE) or its components as described herein.For example, the operations of method 1300 may be performed by a UEcommunications manager as described with reference to FIGS. 5 through 8. In some examples, a UE may execute a set of instructions to controlthe functional elements of the UE to perform the functions describedherein. Additionally or alternatively, a UE may perform aspects of thefunctions described herein using special-purpose hardware.

At 1305, the first UE may determine one or more sidelink DRX parametersfor sidelink communication with a second UE. The operations of 1305 maybe performed according to the methods described herein. In someexamples, aspects of the operations of 1305 may be performed by asidelink DRX component as described with reference to FIGS. 5 through 8.

At 1310, the first UE may transmit, to the second UE, an indication ofthe one or more sidelink DRX parameters, where the indication istransmitted over a sidelink communication link with the second UE. Theoperations of 1310 may be performed according to the methods describedherein. In some examples, aspects of the operations of 1310 may beperformed by a sidelink communications manager as described withreference to FIGS. 5 through 8 .

FIG. 14 shows a flowchart illustrating a method 1400 that supports DRXconfigurations for sidelink in accordance with one or more aspects ofthe present disclosure. The operations of method 1400 may be implementedby a UE 115 (e.g., a first UE) or its components as described herein.For example, the operations of method 1400 may be performed by a UEcommunications manager as described with reference to FIGS. 5 through 8. In some examples, a UE may execute a set of instructions to controlthe functional elements of the UE to perform the functions describedherein. Additionally or alternatively, a UE may perform aspects of thefunctions described herein using special-purpose hardware.

At 1405, the first UE may determine one or more sidelink DRX parametersfor sidelink communication with a second UE. The operations of 1405 maybe performed according to the methods described herein. In someexamples, aspects of the operations of 1405 may be performed by asidelink DRX component as described with reference to FIGS. 5 through 8.

At 1410, the first UE may transmit an indication of a destinationidentity that corresponds to an identity of the second UE, wherein theone or more sidelink discontinuous reception parameters are identifiedbased at least in part on the destination identity. The operations of1410 may be performed according to the methods described herein. In someexamples, aspects of the operations of 1410 may be performed by asidelink DRX component as described with reference to FIGS. 5 through 8.

At 1415, the first UE may transmit, to the second UE, an indication ofthe one or more sidelink DRX parameters, where the indication istransmitted over a sidelink communication link with the second UE. Theoperations of 1415 may be performed according to the methods describedherein. In some examples, aspects of the operations of 1415 may beperformed by a sidelink communications manager as described withreference to FIGS. 5 through 8 .

FIG. 15 shows a flowchart illustrating a method 1500 that supports DRXconfigurations for sidelink in accordance with one or more aspects ofthe present disclosure. The operations of method 1500 may be implementedby a UE 115 (e.g., a first UE) or its components as described herein.For example, the operations of method 1500 may be performed by a UEcommunications manager as described with reference to FIGS. 5 through 8. In some examples, a UE may execute a set of instructions to controlthe functional elements of the UE to perform the functions describedherein. Additionally or alternatively, a UE may perform aspects of thefunctions described herein using special-purpose hardware.

At 1505, the first UE may determine one or more sidelink DRX parametersfor sidelink communication with a second UE. The operations of 1505 maybe performed according to the methods described herein. In someexamples, aspects of the operations of 1505 may be performed by asidelink DRX component as described with reference to FIGS. 5 through 8.

At 1510, the first UE may discontinuously monitor a sidelinkcommunication link for a transmission from the second UE in accordancewith the one or more sidelink DRX parameters. The operations of 1510 maybe performed according to the methods described herein. In someexamples, aspects of the operations of 1510 may be performed by amonitoring component as described with reference to FIGS. 5 through 8 .

FIG. 16 shows a flowchart illustrating a method 1600 that supports DRXconfigurations for sidelink in accordance with one or more aspects ofthe present disclosure. The operations of method 1600 may be implementedby a base station 105 or its components as described herein. Forexample, the operations of method 1600 may be performed by a basestation communications manager as described with reference to FIGS. 9through 12 . In some examples, a base station may execute a set ofinstructions to control the functional elements of the base station toperform the functions described herein. Additionally or alternatively, abase station may perform aspects of the functions described herein usingspecial-purpose hardware.

At 1605, the base station may configure one or more sidelink DRXparameters for sidelink communication between a first UE and a second UEover a sidelink communication link. The operations of 1605 may beperformed according to the methods described herein. In some examples,aspects of the operations of 1605 may be performed by a sidelink DRXconfiguration manager as described with reference to FIGS. 9 through 12.

At 1610, the base station may transmit, to the first UE, a messageindicating the one or more sidelink DRX parameters. The operations of1610 may be performed according to the methods described herein. In someexamples, aspects of the operations of 1610 may be performed by anindication manager as described with reference to FIGS. 9 through 12 .

The following provides an overview of examples of the presentdisclosure.

Example 1: A method for wireless communication at a first UE,comprising: determining one or more sidelink discontinuous receptionparameters for sidelink communication with a second UE; andtransmitting, to the second UE, an indication of the one or moresidelink discontinuous reception parameters, wherein the indication istransmitted over a sidelink communication link with the second UE.

Example 2: The method of example 1, wherein determining the one or moresidelink discontinuous reception parameters comprises: receiving, from abase station, a message indicating the one or more sidelinkdiscontinuous reception parameters for the second UE.

Example 3: The method of any of examples 1 through 2 wherein determiningthe one or more sidelink discontinuous reception parameters comprises:selecting the one or more sidelink discontinuous reception parametersfrom a set of sidelink discontinuous reception parameters for the secondUE.

Example 4: The method of any of examples 1 through 3, whereintransmitting the indication of the one or more sidelink discontinuousreception parameters comprises: transmitting an indication of adestination identity that corresponds to an identity of the second UE,wherein the one or more sidelink discontinuous reception parameters areidentified based at least in part on the destination identity.

Example 5: The method of any of examples 1 through 4, whereintransmitting the indication of the one or more sidelink discontinuousreception parameters comprises: transmitting the indication to thesecond UE via sidelink control information, or a MAC control element, ora combination thereof.

Example 6: The method of example 6, further comprising: transmitting thedownlink control information to the second UE on a physical sidelinkcontrol channel.

Example 7: The method of any of examples 1 through 6, furthercomprising: transmitting a message to the second UE in accordance withthe one or more sidelink discontinuous reception parameters.

Example 8: The method of any of examples 1 through 7, furthercomprising: receiving, from a base station, an indication of one or morediscontinuous reception parameters for communicating with the basestation, wherein the one or more discontinuous reception parameters aredifferent from the one or more sidelink discontinuous receptionparameters; and discontinuously monitoring for a transmission from thebase station in accordance with the one or more discontinuous receptionparameters.

Example 9: The method of example 8, wherein discontinuously monitoringfor the transmission from the base station comprises: powering down afirst power amplifier for communicating with the base station inaccordance with the one or more discontinuous reception parameters, themethod further comprising: powering down a second power amplifier forthe sidelink communication link in accordance with the one or moresidelink discontinuous reception parameters.

Example 10: The method of any of examples 8 through 9, whereinrespective configurations of the one or more discontinuous receptionparameters and the one or more sidelink discontinuous receptionparameters are based at least in part on a first carrier forcommunicating with the base station and a second carrier for thesidelink communication link, a first frequency range for communicatingwith the base station and a second frequency range for the sidelinkcommunication link, one or more bands of a primary land mobile networkfor the sidelink communication link, or a combination thereof.

Example 11: The method of any of examples 1 through 10, furthercomprising: receiving, from a base station, an indication of one or morediscontinuous reception parameters for communicating with the basestation, wherein the one or more discontinuous reception parameters arethe same as the one or more sidelink discontinuous reception parameters;and discontinuously monitoring for a transmission from the base stationin accordance with the one or more discontinuous reception parameters.

Example 12: The method of any of examples 1 through 11, wherein the oneor more sidelink discontinuous reception parameters comprises an ONduration, an offset duration, an inactivity timer, one or more cycledurations, a cycle timer, or any combination thereof.

Example 13: The method of any of examples 1 through 12, wherein thefirst UE is within a coverage area of a base station.

Example 14: The method of any of examples 1 through 13, wherein thefirst UE and the second UE are outside a coverage area of a basestation.

Example 15: A method for wireless communication at a first UE,comprising: determining one or more sidelink discontinuous receptionparameters for sidelink communication with a second UE; anddiscontinuously monitoring a sidelink communication link for atransmission from the second UE in accordance with the one or moresidelink discontinuous reception parameters.

Example 16: The method of example 15, further comprising: receiving,from the second UE, an indication of the one or more sidelinkdiscontinuous reception parameters, the indication received over thesidelink communication link, wherein the one or more sidelinkdiscontinuous reception parameters are determined based at least in parton the received indication.

Example 17: The method of example 16, further comprising: receiving theindication of the one or more sidelink discontinuous receptionparameters from the second UE via sidelink control information, or a MACcontrol element, or a combination thereof.

Example 18: The method of example 16, further comprising: receiving thedownlink control information from the second UE on a physical sidelinkcontrol channel.

Example 19: The method of any of examples 15 through 18, furthercomprising: receiving, from a base station, a message indicating the oneor more sidelink discontinuous reception parameters for the second UE,wherein the one or more sidelink discontinuous reception parameters aredetermined based at least in part on the received indication.

Example 20: The method of any of examples 15 through 19, furthercomprising: identifying the one or more sidelink discontinuous receptionparameters based at least in part on a destination identitycorresponding to an identity of the first UE, wherein discontinuouslymonitoring the sidelink communication link is based at least in part onidentifying the one or more sidelink discontinuous reception parameters.

Example 21: The method of any of examples 15 through 20, wherein the oneor more sidelink discontinuous reception parameters comprises an ONduration, an offset duration, an inactivity timer, one or more cycledurations, a cycle timer, or any combination thereof.

Example 22: The method of any of examples 15 through 21, wherein thefirst UE is outside a coverage area of a base station.

Example 23: A method for wireless communication at a base stationcomprising: configuring one or more sidelink discontinuous receptionparameters for sidelink communication between a first user equipment(UE) and a second UE over a sidelink communication link; andtransmitting, to the first UE, a message indicating the one or moresidelink discontinuous reception parameters.

Example 24: The method of example 23, wherein transmitting the messageindicating the one or more sidelink discontinuous reception parameterscomprises: determining an identity of the second UE; and transmitting,as part of the message, an indication of a destination identity thatcorresponds to the identity of the second UE, wherein the one or moresidelink discontinuous reception parameters are identified based atleast in part on the destination identity.

Example 25: The method of any of examples 23 through 24, furthercomprising: transmitting, to the second UE, a second message indicatingthe one or more sidelink discontinuous reception parameters.

Example 26: The method of any of examples 23 through 25, furthercomprising: configuring one or more discontinuous reception parametersfor communicating with the first UE, wherein the one or morediscontinuous reception parameters are different from the one or moresidelink discontinuous reception parameters; and transmitting, to thefirst UE, an indication of the one or more discontinuous receptionparameters.

Example 27: The method of example 26, wherein: respective configurationsof the one or more discontinuous reception parameters and the one ormore sidelink discontinuous reception parameters are based at least inpart on a first carrier for communicating with the base station and asecond carrier for the sidelink communication link, a first frequencyrange for communicating with the base station and a second frequencyrange for the sidelink communication link, one or more bands of aprimary land mobile network for the sidelink communication link, or acombination thereof.

Example 28: The method of any of examples 23 through 27, furthercomprising: configuring one or more discontinuous reception parametersfor communicating with the first UE, wherein the one or morediscontinuous reception parameters are the same as the one or moresidelink discontinuous reception parameters; and transmitting, to thefirst UE, an indication of the one or more discontinuous receptionparameters.

Example 29: The method of any of examples 23 through 28, wherein the oneor more sidelink discontinuous reception parameters comprises an ONduration, an offset duration, an inactivity timer, one or more cycledurations, a cycle timer, or any combination thereof.

Example 30: The method of any of examples 23 through 29, wherein thefirst UE is within a coverage area of the base station and the second UEis outside the coverage area of the base station.

Example 31: An apparatus for wireless communication comprising at leastone means for performing a method of any one of the examples 1 through14.

Example 32: An apparatus for wireless communication comprising at leastone means for performing a method of any one of the examples 15 through22.

Example 33: An apparatus for wireless communication comprising at leastone means for performing a method of any one of the examples 23 through30.

Example 34: An apparatus for wireless communication comprising aprocessor and memory coupled to the processor, the processor and memoryconfigured to perform a method of any one of examples 1 through 14.

Example 35: An apparatus for wireless communication comprising aprocessor and memory coupled to the processor, the processor and memoryconfigured to perform a method of any one of examples 15 through 22.

Example 36: An apparatus for wireless communication comprising aprocessor and memory coupled to the processor, the processor and memoryconfigured to perform a method of any one of examples 23 through 30.

Example 37: A non-transitory computer-readable medium storing code forwireless communication, the code comprising instructions executable by aprocessor to perform a method of any one of examples 1 through 14.

Example 38: A non-transitory computer-readable medium storing code forwireless communication, the code comprising instructions executable by aprocessor to perform a method of any one of examples 15 through 22.

Example 39: A non-transitory computer-readable medium storing code forwireless communication, the code comprising instructions executable by aprocessor to perform a method of any one of examples 23 through 30.

It should be noted that the methods described herein describe possibleimplementations, and that the operations and the operations may berearranged or otherwise modified and that other implementations arepossible. Further, aspects from two or more of the methods may becombined.

Although aspects of an LTE, LTE-A, LTE-A Pro, or NR system may bedescribed for purposes of example, and LTE, LTE-A, LTE-A Pro, or NRterminology may be used in much of the description, the techniquesdescribed herein are applicable beyond LTE, LTE-A, LTE-A Pro, or NRnetworks. For example, the described techniques may be applicable tovarious other wireless communications systems such as Ultra MobileBroadband (UMB), Institute of Electrical and Electronics Engineers(IEEE) 802.11 (Wi-Fi), IEEE 802.16 (WiMAX), IEEE 802.20, Flash-OFDM, aswell as other systems and radio technologies not explicitly mentionedherein.

Information and signals described herein may be represented using any ofa variety of different technologies and techniques. For example, data,instructions, commands, information, signals, bits, symbols, and chipsthat may be referenced throughout the description may be represented byvoltages, currents, electromagnetic waves, magnetic fields or particles,optical fields or particles, or any combination thereof.

The various illustrative blocks and modules described in connection withthe disclosure herein may be implemented or performed with ageneral-purpose processor, a DSP, an ASIC, a CPU, an FPGA or otherprogrammable logic device, discrete gate or transistor logic, discretehardware components, or any combination thereof designed to perform thefunctions described herein. A general-purpose processor may be amicroprocessor, but in the alternative, the processor may be anyprocessor, controller, microcontroller, or state machine. A processormay also be implemented as a combination of computing devices (e.g., acombination of a DSP and a microprocessor, multiple microprocessors, oneor more microprocessors in conjunction with a DSP core, or any othersuch configuration).

The functions described herein may be implemented in hardware, softwareexecuted by a processor, firmware, or any combination thereof. Ifimplemented in software executed by a processor, the functions may bestored on or transmitted over as one or more instructions or code on acomputer-readable medium. Other examples and implementations are withinthe scope of the disclosure and appended claims. For example, due to thenature of software, functions described herein may be implemented usingsoftware executed by a processor, hardware, firmware, hardwiring, orcombinations of any of these. Features implementing functions may alsobe physically located at various positions, including being distributedsuch that portions of functions are implemented at different physicallocations.

Computer-readable media includes both non-transitory computer storagemedia and communication media including any medium that facilitatestransfer of a computer program from one place to another. Anon-transitory storage medium may be any available medium that may beaccessed by a general-purpose or special purpose computer. By way ofexample, and not limitation, non-transitory computer-readable media mayinclude RAM, ROM, electrically erasable programmable ROM (EEPROM), flashmemory, compact disk (CD) ROM or other optical disk storage, magneticdisk storage or other magnetic storage devices, or any othernon-transitory medium that may be used to carry or store desired programcode means in the form of instructions or data structures and that maybe accessed by a general-purpose or special-purpose computer, or ageneral-purpose or special-purpose processor. Also, any connection isproperly termed a computer-readable medium. For example, if the softwareis transmitted from a website, server, or other remote source using acoaxial cable, fiber optic cable, twisted pair, digital subscriber line(DSL), or wireless technologies such as infrared, radio, and microwave,then the coaxial cable, fiber optic cable, twisted pair, DSL, orwireless technologies such as infrared, radio, and microwave areincluded in the definition of computer-readable medium. Disk and disc,as used herein, include CD, laser disc, optical disc, digital versatiledisc (DVD), floppy disk and Blu-ray disc where disks usually reproducedata magnetically, while discs reproduce data optically with lasers.Combinations described herein are also included within the scope ofcomputer-readable media.

As used herein, including in the claims, “or” as used in a list of items(e.g., a list of items prefaced by a phrase such as “at least one of” or“one or more of”) indicates an inclusive list such that, for example, alist of at least one of A, B, or C means A or B or C or AB or AC or BCor ABC (i.e., A and B and C). Also, as used herein, the phrase “basedon” shall not be construed as a reference to a closed set of conditions.For example, an example operation that is described as “based oncondition A” may be based on both a condition A and a condition Bwithout departing from the scope of the present disclosure. In otherwords, as used herein, the phrase “based on” shall be construed in thesame manner as the phrase “based at least in part on.”

In the appended figures, similar components or features may have thesame reference label. Further, various components of the same type maybe distinguished by following the reference label by a dash and a secondlabel that distinguishes among the similar components. If just the firstreference label is used in the specification, the description isapplicable to any one of the similar components having the same firstreference label irrespective of the second reference label, or othersubsequent reference label.

The description set forth herein, in connection with the appendeddrawings, describes example configurations and does not represent allthe examples that may be implemented or that are within the scope of theclaims. The term “example” used herein means “serving as an example,instance, or illustration,” and not “preferred” or “advantageous overother examples.” The detailed description includes specific details forthe purpose of providing an understanding of the described techniques.These techniques, however, may be practiced without these specificdetails. In some instances, well-known structures and devices are shownin block diagram form in order to avoid obscuring the concepts of thedescribed examples.

The description herein is provided to enable a person skilled in the artto make or use the disclosure. Various modifications to the disclosurewill be readily apparent to those skilled in the art, and the genericprinciples defined herein may be applied to other variations withoutdeparting from the scope of the disclosure. Thus, the disclosure is notlimited to the examples and designs described herein, but is to beaccorded the broadest scope consistent with the principles and novelfeatures disclosed herein.

1. (canceled)
 2. An apparatus for wireless communication at a first userequipment (UE), comprising: a processor; and memory coupled to theprocessor, the memory comprising instructions executable by theprocessor to cause the apparatus to: receive, from a second UE, a firstmessage indicating one or more discontinuous reception parameters;determine a sidelink discontinuous reception configuration for sidelinkcommunications with the second UE, wherein the sidelink discontinuousreception configuration is based at least in part on the one or morediscontinuous reception parameters; and transmit, to the second UE, asecond message indicating the sidelink discontinuous receptionconfiguration over a sidelink communication link with the second UE. 3.The apparatus of claim 2, wherein the instructions are furtherexecutable by the processor to cause the apparatus to: transmit, to anetwork device, a third message indicating the one or more discontinuousreception parameters based at least in part on receiving the firstmessage from the second UE.
 4. The apparatus of claim 3, wherein theinstructions are further executable by the processor to cause theapparatus to: receive, from the network device, a control message thatschedules one or more resources for the sidelink communications with thesecond UE.
 5. The apparatus of claim 3, wherein the first UE is in anRRC connected mode.
 6. The apparatus of claim 2, wherein theinstructions to transmit the second message are executable by theprocessor to cause the apparatus to: transmit the second message to thesecond UE via radio resource control signaling.
 7. The apparatus ofclaim 2, wherein the sidelink discontinuous reception configurationcomprises at least a discontinuous reception cycle start timer, adiscontinuous reception inactivity timer, a discontinuous reception ONduration timer, and a discontinuous reception slot offset.
 8. Theapparatus of claim 2, wherein the sidelink discontinuous receptionconfiguration is based at least in part on a carrier for the sidelinkcommunication link, a frequency range the sidelink communication link,one or more bands of a primary land mobile network for the sidelinkcommunication link, or a combination thereof.
 9. The apparatus of claim2, wherein the instructions are further executable by the processor tocause the apparatus to: receive, from a network device, an indication ofa discontinuous reception configuration for communicating with thenetwork device, wherein the discontinuous reception configuration isdifferent from the sidelink discontinuous reception configuration. 10.The apparatus of claim 2, wherein the instructions are furtherexecutable by the processor to cause the apparatus to: receive, from anetwork device, an indication of a discontinuous reception configurationfor communicating with the network device, wherein the discontinuousreception configuration is equivalent to the sidelink discontinuousreception configuration.
 11. The apparatus of claim 2, wherein theinstructions are further executable by the processor to cause theapparatus to: transmit a message to the second UE in accordance with thesidelink discontinuous reception configuration.
 12. The apparatus ofclaim 2, wherein the second UE is outside a coverage area of a networkdevice.
 13. A method for wireless communication at a first userequipment (UE), comprising: receiving, from a second UE, a first messageindicating one or more discontinuous reception parameters; determining asidelink discontinuous reception configuration for sidelinkcommunications with the second UE, wherein the sidelink discontinuousreception configuration is based at least in part on the one or morediscontinuous reception parameters; and transmitting, to the second UE,a second message indicating the sidelink discontinuous receptionconfiguration over a sidelink communication link with the second UE. 14.The method of claim 13, further comprising: transmitting, to a networkdevice, a third message indicating the one or more discontinuousreception parameters based at least in part on receiving the firstmessage from the second UE.
 15. The method of claim 14, furthercomprising: receiving, from the network device, a control message thatschedules one or more resources for the sidelink communications with thesecond UE.
 16. The method of claim 14, wherein the first UE is in an RRCconnected mode.
 17. The method of claim 13, wherein transmitting thesecond message comprises: transmitting the second message to the secondUE via radio resource control signaling.
 18. The method of claim 13,wherein the sidelink discontinuous reception configuration comprises atleast a discontinuous reception cycle start timer, a discontinuousreception inactivity timer, a discontinuous reception ON duration timer,and a discontinuous reception slot offset.
 19. The method of claim 13,wherein the sidelink discontinuous reception configuration is based atleast in part on a carrier for the sidelink communication link, afrequency range the sidelink communication link, one or more bands of aprimary land mobile network for the sidelink communication link, or acombination thereof.
 20. The method of claim 13, further comprising:receiving, from a network device, an indication of a discontinuousreception configuration for communicating with the network device,wherein the discontinuous reception configuration is different from thesidelink discontinuous reception configuration.
 21. The method of claim13, further comprising: receiving, from a network device, an indicationof a discontinuous reception configuration for communicating with thenetwork device, wherein the discontinuous reception configuration isequivalent to the sidelink discontinuous reception configuration. 22.The method of claim 13, further comprising: transmitting a message tothe second UE in accordance with the sidelink discontinuous receptionconfiguration.
 23. The method of claim 13, wherein the second UE isoutside a coverage area of a network device.
 24. An apparatus forwireless communication at a first user equipment (UE), comprising: meansfor receiving, from a second UE, a first message indicating one or morediscontinuous reception parameters; means for determining a sidelinkdiscontinuous reception configuration for sidelink communications withthe second UE, wherein the sidelink discontinuous receptionconfiguration is based at least in part on the one or more discontinuousreception parameters; and means for transmitting, to the second UE, asecond message indicating the sidelink discontinuous receptionconfiguration over a sidelink communication link with the second UE. 25.The apparatus of claim 24, further comprising: means for transmitting,to a network device, a third message indicating the one or morediscontinuous reception parameters based at least in part on receivingthe first message from the second UE.
 26. The apparatus of claim 25,further comprising: means for receiving, from the network device, acontrol message that schedules one or more resources for the sidelinkcommunications with the second UE.
 27. The apparatus of claim 25,wherein the first UE is in an RRC connected mode.
 28. The apparatus ofclaim 24, wherein the means for transmitting the second messagecomprises: means for transmitting the second message to the second UEvia radio resource control signaling.
 29. The apparatus of claim 24,wherein the sidelink discontinuous reception configuration comprises atleast a discontinuous reception cycle start timer, a discontinuousreception inactivity timer, a discontinuous reception ON duration timer,and a discontinuous reception slot offset.
 30. The apparatus of claim24, wherein the sidelink discontinuous reception configuration is basedat least in part on a carrier for the sidelink communication link, afrequency range the sidelink communication link, one or more bands of aprimary land mobile network for the sidelink communication link, or acombination thereof.
 31. A non-transitory computer-readable mediumstoring code for wireless communication, the code comprisinginstructions executable by a processor to: receive, from a second UE, afirst message indicating one or more discontinuous reception parameters;determine a sidelink discontinuous reception configuration for sidelinkcommunications with the second UE, wherein the sidelink discontinuousreception configuration is based at least in part on the one or morediscontinuous reception parameters; and transmit, to the second UE, asecond message indicating the sidelink discontinuous receptionconfiguration over a sidelink communication link with the second UE.